Am I bi? or am I too young?

okay..so I'm a female thirteen y.o and honestly I've liked girls since I was ten. By then I was watching lesbian porn and everything lol. At 11, I had a waterfall in my pants when my cousin decided to sleep topless because it was so hot (she's oddly..open). I like the look of a woman's body..it fascinates me and not to mention turns me on. Oh but don't get me wrong I like guys too. But anyway, recently a few super amazingly hot girls in my grade have started confessing their bisexuality. And at a sleepover last weekend, one of my best-friends confessed to me she was bi, and asked if I was too. I couldn't tell if she liked me..but I told her no because I wasn't ready to completely label myself. But I sorta kinda like her..ish. lol, I mean that I don't WANT a relationsip with her, but a make-out session wouldn't be turned down ya know? I fantasize all the time about girls, and have even gotten off to a few of my friends' rather exposing photos.. I feel so dirty but I just crave females. Males aren't enough anymore, I need both. So...what should I tell my friends who demand an answer? Should I go out with it, or tell them I'm not sure yet? I'd like to come out..but I'm also scared of what my parents and family will say... Or is it normal to feel this way yet still possibly be straight? ugh I don't even know please help :(