Bisexuality or human instinct/hormones?

Recently, I've been thinking about my sexuality and what genders I'm more interested in. Ultimately I believe I'm a lesbian or will be when I get older. Most of the time I find it hard to be physically or even emotionally attracted to a guy. There are very few males that actually spark my attraction, but whenever I see a woman I, most of the time, am automatically attracted (physically) to them. There are very few women that I am NOT attracted to. Big, skinny, short, tall, lanky, nerdy, sporty, preppy, "scene/emo", you name it I'm probably into that type of a woman (except for butch sometimes, though). Anyways, (Sorry attention span of a 16 year old girl here!) I feel like because I have hormones and teenage years are usually the nearing high-point of human reproductive instinct, that I'm only attracted or think about men at times because it's human nature to desire to "reproduce" at such a young "in-between" age. I don't get turned on by "straight porn" only lesbian. I don't really even picture myself marrying a man and being happy. I dream of marrying a nice woman and coming home to her every day. So, is this just my hormones making me like men or am I truly bisexual-just more into females?