Why didnt she even say hi to me?

hi, today the gir i liked just walked past me like nothin...i told her i liked her like a month ago...the day after that she just kept teasing at me by smiling at me all day..then after a week she just completely ignored me and tried making me jealous...today she didnt even say hi, we only stared at each other for a second while we were watching a movie in class laughing...i was about to ask her to be my gf but then i pussied out...so why is she mad...i dont remember doing anythig wrong...yesterday i askedwhy she has been giving me the cold shoulder and she replied 'lmao shut up its too early'