Gosh, you have a lot going on in your head. I will agree completely with Paxiled. The only counter point I have is that questioning if you are gay or not and having mixed feelings about the suspicion that you are can create emotions. In some countries, being gay is illegal. Sounds kind of strange to me but even in America, we sadly still have prejudice that can make it the less easy road to travel for some. Church, parents, society can make someone have a difficult time than they should for loving who they love. Sad reality. But everyone has to be who they are in my opinion and who they are is okay. Fine even. Even good. But the struggle to figure it out can be real. I have teens and some days they struggle with their identity and not liking themselves. I think it is a phase for some people. Adding in their questioning their sexuality, ya. They can get anxious and self conscious (pretty normal at a certain age). And because we all have random thoughts in our heads, some think that means that they ARE this or that when they are just thoughts. I think we can have fantasies and whatnot and that's all it is. It doesn't mean you will marry someone of the same sex just because you fantasized about it some. Or even had some experimental episodes with them. That's just my take on it.
Anyway, have you ever considered talking to a psychologist/therapist? They can be really great at working through issues we 'wonder about' within ourselves. They are supposed to be a no judgement zone, so you can freely talk there when you might not tell everyone in your daily life these things.
OCD is a medical condition. People often misuse the term to describe other things. Keep that in mind. Having strong thoughts might not be OCD. Anxiety all in itself may cause intrusive thoughts. So, this again would be helpful to talk to someone about. Do these thoughts tempt you to do something you'd otherwise not want to do or are they just thoughts?
If you were the same age you were also a kid, so unless you were the ringleader and they all followed you blindly you were all equally involved. Given the percentage of people who are gay, it would be odd if a couple of you weren't gay to begin with. You don't cause gay -- gay just is. Given that being gay is just as fine as not being gay, why would you be guilty of "causing" someone to become gay? This is the problem with that thing they're calling HOCD. It isn't really a thing. It's giving in to a centuries old bias against being gay and letting it become an obsession, even if we're not overtly aware of having it. Gay people have it as well, which is why so many have such a difficult time being gay. It's going to take a long time to overcome that period of our history when major religions began to persecute gay people; before that, it appears that homosexuality was common and bisexuality was more the norm. Most people don't know this history, or they know it and just don't think about it, but if you study the ancient Greeks and the Romans etc. there's a lot of homosexuality there and it's both accepted and often idealized. Norms change. If you can accept gay as okay, it's hard to see how anyone would have this thing called HOCD. Peace.