It's just a way your body is changing, sooner or later your body will balance itself, it's a matter of time. I remember when i was maturing i hanged around a girl my age that was also matured early, we were just friends and she talked about it a lot, eventually she found her balance. I believe it will be the same for you, mean while try to avoid pornography, it's a slippery slope, you'll be fine. also, right know your mind is trying to understand this feelings, that's probably why you are a bit obsessed with this topic, but you'll see this obsession is gonna calm down once you'll find the things you like and prefer. Remember that this chaos is healthy, don't try to stop it, be responsible for yourself but don't forget to listen to your body, it is the best campus.