How to bring up to my wife that she's gone too far on a prank?

Alright, so. I'm a little new to Dating.mobi, never made an account here before, mostly use this site to browse some hobbyist Forum Sections or find links to pirated movies. I've lurked enough to know that a couple of pairs of new eyes on any situation could bring some good insight, so here goes. The last 5 years were tough for me and the wife. It was better for a bit, but yesterday it got seriously weird again. I need someone to tell me whether I'm overreacting or not.
My wife's [34F] a biotech engineer, and I'm [39M] a self-employed artist (I mostly do freelance installations, but I've been branching out into murals on the side), so we've never been really able to talk to each other about our work. In 2017, she picked up a government contract and had to sign some sort of NDA stopping her from talking about her job at all. Combined with the weird hours, and the long shifts, and the times she had to fly all the way out to Santa Rosa for some kind of week-long conference, it had been really hard to keep anything going between us. Anyone who's been in a long-distance relationship or had a spouse or partner relocate somewhere else knows how hard it can be to keep a connection going.
She was clearly tired all the time, with none of that spark that kept us both going through education and the tedious crawl of job searching for the first time. She even came back one week and had a breakdown in my arms about how she wasn't sure she wanted to continue in her field of study anymore and if what she was doing was right. Like I said, my wife can't tell me specifics about her job, so I assume she was taking the tedium and exhaustion really poorly and wishes she took a job that was better for her, like mechanical repair - she's always been really into automobile restoration.
Anyway, uhm, we did sit down and have a good conversation about where to go from there. We ended up going to the couple's therapy session that my wife's colleague recommended and was covered by her workplace insurance. Stopped going after two sessions because of the conflict with my wife's work schedule, but the advice we got was great! He asked us to think about what we loved about each other and what drew us to each other in the first place, and we both agreed it was that playful spark of us in college and how easily we'd take a joke and spin it out into an elaborate little world that no one but the two of us were privy to. He suggested that we bring some of that on-the-spot whimsy back after my wife returned from her conference.
So you know, we started pulling small pranks on each other. I'd spend an hour or two in Photoshop and print out a label, then the next day she'd go out the front door and discover we'd accidentally received a package of "Premium-Grade Fresh Air" that was supposed to be delivered to Atlantis, Georgia. She'd take some of her official workplace stickers and slap a "Biohazard - Dispose" or "Dangerous If Swallowed" label on my favorite brand of sunflower seeds or take all my multivitamin gummies and put them into an official-looking "Class 5 - Psychotropes" bottle.
We'd come into the room and start talking seriously about how strange it was that they found Gruyere cheese on the moon, couldn't anyone see that it was just branding and it was actually aged cheddar? Some of the stuff was really elaborate too, like - I went all out with the time I glued all our (outdated, don't worry!) kitchen utensils and furniture to the ceiling so it looked like we were upside down in the house, but I still can't figure out to this day how she did some of the stuff she did! There was this time her silhouette in the corner of my vision seemed warped for a couple of days, although she looked perfectly normal every time I turned around to look at her face-on. Some kind of foam padding or a shaped wig, I'd guess.
Things went great for a while and got even better after her project wrapped up and she was able to come back home properly and just... relax. She said she'd been given a 3-week paid vacation after the project which sounded a little strange to me, but I've never been properly employed by a company on a contract so I was just glad to have my wife back with me.
I asked her again what she had been working on, but this time she just smiled and told me to ask again in ten years. We got Indian takeout that night, but she gave me all her Madras curry, which I thought was weird at the time because she's always loved spice. She told me it was because she was cultivating a new tongue implant that had to incubate for 30 days before it could be harvested, though, so that set us off on another back-and-forth romp about the various body parts we were growing ( we decided my hand was an experimental limb infused with rhino DNA) and I forgot all about it.
Anyway, the pranks didn't stop now that she was back at home. I assumed that since we have more time to spend together now, we'd just... fall back into the natural state of affairs we had before she took the job? But she kept blanking out at certain times, keeping me on my toes around the house. She doesn't seem to remember a lot of the inside jokes we had back in college. Once I saw her having what seemed like a pretty normal Zoom meeting with a colleague in her office, but it still kind of gives me chills to think about. She was speaking straight gibberish at the screen, but he was nodding and talking back like he could understand every word.
Some of the pranks aren't even really funny, they're just strange and I don't get what she was trying to go for. I found a microSD card between the sofa cushions when I was deep cleaning the other day, and I plugged it in to check out what was inside. It was just a 6 hour shaky closeup video of what looked like industrial tile, focusing on one of those endless motion flamingo desk toys? And there was nothing but shaky breathing and that desk toy, and my wife's hand reaching out to get it moving again every so often, for the entire 6 hours. Just shaky footage of that click-clacking desk toy, like she was afraid to focus the camera anywhere else.
Anyway, that's what brings us to what I'm here to talk about. Sorry for the long ramble up there, but I feel like that background is necessary for why I'm reacting the way I am. I got a package in the mail yesterday, and it contained a little USB drive and a handwritten letter from my wife. The letter said that it was a secure failsafe that she had set up with her attorneys years ago, and it was supposed to be sent to her spouse and family members after she didn't check in with them for over 5 years, presumably in case of death.
I was a little wary about plugging in the USB drive, but I googled how to set up a sandbox on my laptop in case it had a virus or something. I didn't need to worry. All of it was just legal wills and records, and an honestly very sweet photo gallery of her favorite childhood memories, her family, and me, dated from before 2017.
I guess she wanted to give me a present and show me the good times we've had together, but why 2017? And am I wrong for feeling like she stepped over a line here? I appreciate the sentiment but I can't be the only one to feel like the delivery was in poor taste. I'm a pretty nervous person in general. These things have always scared me and I really didn't like reading a letter from my wife where the first sentence in it was "If you're reading this, I've passed away."
I still haven't talked to her about it, because I'm not sure how to bring it up. I'm hoping you guys will have some advice for me. I'm typing this up from my phone right now because I'm still awake, and my wife's in bed with me.
She's gone to sleep already, breathing deep and even and smooth, but I'm not sure I want to stay with her here for the rest of the night. Mostly because when I sat down to read that letter at the kitchen table, her handwritten grocery list was right next to me. It made me realize that she never used to cross her t's.


Source.