Are you an ugly, dumb and mentally challenged guy weighing 350 pounds?
If not, then MAN UP.
Stop being such a bitch, call her if you are interested in her. When in her company, talk to her, make her laugh, don't stay in the back. How are you supposed to win her over without doing ANYTHING??
Cmon man, get your act together.
She's obviously attracted to you, but if you act like this you'll both end up feeling stupid.