Right now I have this big crush on a girl, I've even had two dreams about her. But it's strange bc last school year ,I'm in 10th grade btw, I had a crush on a guy and I would always get nervous around him and all that stuff you do when you have a crush on someone. But in the summer I all of a sudden started wondering if I was a lesbian. Now I have a crush on a girl, whos a lesbian, who I honestly can not get my mind off. And all that 'stuff you do' with a crush happens to me when I'm around her.
It means you have a crush on her. And that's cool. You seem capable of romantic feelings for guys and girls. You're not necessarily a lesbian, you might be bisexual. You might be straight but very curious. Or you might be a lesbian. It's normal to be confused, and you shouldn't worry about it. There's nothing wrong with questioning yourself. I'd suggest you just enjoy your crush for the moment and try not to worry too much. Are you interested in having something with her? Do you want to kiss her? Go on a date? If you find that you are, you could eventually make a move. If this girl is your friend, you could also just tell her you're questioning. It's often easier to talk about these subjects with someone who can directly relate, and talking to someone can really help, especially someone who can answer your questions.
For me, it was my best girl friend. We both realized we felt that way with each other back in high school. We ended up experimenting with each other for a while until I went away to college.