Really confused about my sexuality

One of my friends kinda let himself go but I was looking at an old picture of him on the fridge and I almost let it slip and thought "wow! he used to be really cute". I have a lot of these moments where I will see a guy and think he's cute and even fantasize about them.The thing is, and I'm about to get a little graphic here, is that I can fantasize about guys but I have to stop right before I blow my load because it feels wrong. is this just social programming?also I experimented a little when I was younger (12 years old or so) and didn't really have any issues with it, I actually found it kinda fun. Any thoughts you guys?