IMO anytime religion puts very strict and repressive rules, this causes problems. Repression often has the opposite affect. Humans are sexual beings, so sex just for procreation is unreasonable. I had a brother who was gay(deceased now) and don't believe its wrong. Some teenagers feel confused about their sexuality, especially since you've view porn quite a bit -you might wonder why gay porn affects you a certain way. Some also believe sexuality is fluid but its not for everyone. If you haven't had a real life experience, this is another factor. Try not worry and don't let religion stress you out more.