Fianc? accidentally said I?m not the ?only one?

My 31F fiance 35M recently got engaged and have been together for almost 3 years. We?ve never had any trust issues and are very close/connected. We spend most of our free time together.
He works from home and I?ve noticed he?s been closing his office door where he used to leave it open. He?s explained that it helps him focus better with work.
Today I opened his office door to chat with him and I could tell I startled him. He had a guilty look on his face and picked up his phone. He closed what he had open on his phone which prompted me to ask him what he was doing. Innocently enough, he showed me he was listening to ASMR (an Asian woman in a doctor?s office). Me: ?why do you seem off like I caught you doing something? Were you doing something inappropriate??
Him: ?no honey, I was not doing anything APPROPRIATE?
Me: (thinking ?he meant to say inappropriate but no need to correct him since i understand what he?s meaning to say?)
Him: ?My honey doesn?t like when she?s not the only one?
This statement was immediately off putting to me and he realized that and quickly apologized and said his words came out wrong. I have a strange feeling though and I feel hurt by this comment. I can?t shake wondering if this was two ?Freudian slips? back to back.
I?m confused and I am not sure if this is a red flag or if I should accept his apology and move on. I sometimes have a tendency of being an overthinker.
We have each other?s passwords but rarely need to use each other?s phones. He?s been hesitant in the past at times when I?ve tried to show him how to do things on his phone and whatnot.
Were these statements alarming or should I simply accept his apology?
TLDR : Fianc? accidentally said I am not the ?only one? and then apologized saying his words came out wrong. Now I am worried that there could be true meaning behind his words.
Edit for clarification: we have a no porn boundary in our relationship for the mere goal of great sex. We?ve never disagreed on this boundary and it was fairly easy to discuss early on in the relationship. I don?t have a problem with my fianc? keeping ASMR to himself and I understand being embarrassed when I learned about this, but I wouldn?t be okay with him sexually fantasizing another person. His bizarre statement made me upset, not the ASMR itself.
Update: Overall I?ve decided I think he was ashamed to admit he was listening to the ASMR and I trust he wasn?t hiding anything sexual. Thank you everyone for helping me sort out these thoughts!


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