Am I gay or is it hocd???

[Hmukri]

So i am a 15 year old male, who until now, has NEVER questioned his sexuality, and I've always known I'm straight. But, suddenly, idk what it was, but something made me have thw thought: am i gay?. Since then, everyday has been a living hell, and i cant seem to get rid of these thoughts that ive somehow been living in denial of being gay and have been gay my whole life. Also, I keep noticing that sudeenly even though i dont like guys, my braon will go like"you know you like him" or "you want him. You know it" and other crap like that. Can hocd do this? False feelings and attractions, whoke simultaneously making me lose attraction to girls? Yeah, I also lost attraction to girls.My question is can you just suddenly turn gay? Also, is it even possoble to have never had a gay thought, and then suddenly realizing your gay? What if this is just me realizing that im gay?  What if all the thoughta of being with a girl were all fake? I'm really freaking out, and everyday I have to check and ask myself if im gay, and i keep trying to find anything that proves im not gay, but the hocs still wont go away, and its becoming a pain. Is it even possible for a thought to turn you gay? Anyways, someone please help me.

[Hmukri]

Plz somebody answer