Why has she stopped talking 2 me?

ok cut a long story short i lke som girl stefinea she is nice and kind we were just frends at first i didnt want her 2 find out i like her coz i like bian her frend we get on betta i think but now i think she has found out i like her and she is avoiding me, ignoring me and i duno wht she is upto can any 1 plzz tell me if this is normal 4 a girl 2 doo?