Sex and other stuff

So I haven’t had sex in a very very long time I would say just a little under a year I had a long term boyfriend and we had amazing sex then I slept with this guy for a bit and it was good but haven’t had sex since and it’s weird cause I like want to but I’m not horny at all the other night I ya know tried to help myself you could say and nothing happened I didn’t even feel anything I’m sure it’s nothing but I’m 18 and idk I wanna have sex so what’s going on?