I sort of understand your feelings. (I don't want to say I completely do since I don't know exactly what they are.) I get the feeling you don't want to be worrying about it and you want to be able to say something to someone else and not have to speak whole paragraphs and give them too much information. That ability to just say "I'm gay" (which lesbians are also so it's fine to say) and have people go "ah, okay" and move on to other things. It makes things simple. But if your feelings aren't so simple it's not so easy.
It's also okay not to know exactly who you are and what you're feeling. Everyone's different. I think lots of people will understand that. I hope you won't over-worry about it. Maybe you just need time to figure it out. You can also just, you know, define yourself as "still thinking about it" or however you want to word it.
But to have to know everything before college? I'm graduated from college and I'm far from knowing and having everything. College (or just being out of high school in general) might be your time to find yourself once you aren't held down by everything you've done and said and that's followed you through your elementary, middle, and high school career. There is no rush to define yourself.