Holy crap, are you me? This sounds exactly like what I was going through around 15-16. Stay strong and remember that a lot of people have all kinds of weird feelings at that age, when you're just getting used to being a sexual creature. Sexuality is confusing and society ties so much of your identity to it, but remember it's not everything you are. And trust me, the older you get, the more secure you'll be with whichever identity you happen to be (sounds to me you're just a straight girl who can appreciate female beauty, which is totally okay). Either way, feel better!