OCD (HOCD)

So this year I was diagnosed with obsessive compulsive disorder and I don't wish this illness on anyone. It's not the checking kind or organizing things. It's more like really bad intrusive thoughts that I can't let go. I am straight and have been straight my entire life but have read lesbian erotica and watched lesbian porn. I've even chatted with two girls online LIKE FOR TWO minutes (I did this because there were no guys online and I was horny, lol). for some reason my mind remembers that I did this three years ago this year and now I can't stop thinking "what if" "what if" and I know I'm not. I'm not attracted to girls and it's driving me nuts. Has anyone else ever been in this situation? I'm 22 years old, I think I would know if I was gay by now.