She Has Me So Confused....Ladies, Help Please??

There is this girl that I have come to like over the last couple months. She has flirted with me endlessly, and wrote "I love you" through one of my notebooks. We also mess with each other, like we will take stuff of each others and hold on to them until the end of the period, or we will throw stuff at each other jokingly. We had a locker clean out one day, and she came with me to my locker and said she was going to help. She also went on a trip and her friend asked if I missed her. She is a cheerleader, and she would always say hi to me on the sideline. A couple days ago, she said that she loved me and that she had a crush on me. She didn't sound very serious, and right after that she said we were BFF's. I've had people ask me whats going on between us, and a teacher even said something about us. At our school, the football players give their jerseys to the girls, and she asked if she could wear mine to the game. However, she said it was because everyone else is a douche, but there are other guys she could have asked that aren't that way. Yesterday, she asked questions like if she was hurt, would I help her, or if someone made her sad, would I give her a shoulder to cry on. The weird thing though, is she is a senior, and I'm a sopre. Do you think she is interested, or are we just good friends?