I need to know if im overreacting..

So this is going to be long and kind of confusing. Just a little backstory; I have a long history of being cheated on especially with people that I know. My fiancé today was talking with me about how I am the only one of my coworkers who has to wear a bra to work because it’s noticeable when I don’t. So he casually says that the next runner-up would be my coworker we’ll call her Jane... well he proceeds to say he was watching a porn video last night that had a girl who looked alot like jane. It got me a little upset... when he noticed i was upset he immediately gets upset.. starts saying how hes a douche bag, how he guesses he shouldnt watch porn (its something im 1000% cool with) and just ultimately acts like im being bitchy.. am I overreacting for being upset? We’ve had issues with him takking to girls hes tried sleeping with and he’s constantly deleting his history on things.. at one point he was on a porn site and on google trying to find sex tapes of me.. when i asked him why he got defensive.. he started deleting conversations between him and females ... im starting to get a bad gut feeling