She gives signs that she both likes and dislikes me? why?

[Alcatraz]

There is this girl in school. We first saw each other at the gym but i didnt make a move. Later i said Hi in school but i didnt start a conversation. Then i added her on facebook but she wasnt interested in much chatting and was sort of fishy towards me. Now she removed me from facebook when i asked her to go to the gym. I thought she didnt like me but then i went in school next to her and said HI, whatcha doing? I also asked some stupid questions and she was laughing (she laughs often), but at the same time she didnt flirt back. We went to the same school lesson and did a test with a bunch of other people inside the classroom and saw each other and she seemed to be purposely avoiding looking at me (shy girls do it). Now she has given me signs of attraction and repulsiveness and idk what to think. Is she playing a trick? being too shy or just not interested? any suggestions?
I am Capricorn man and she is Virgo woman