my girlfriend use diane pills for the first time. she already finished the 21 tablet. but what we are wondering now is until now she doesn't have her menstration yet. we have 2 times unprotected sexual intercourse for 3 times during her first week of taking pill. is it possible that she is pregnant, becausse we are planning her to stop taking pill and use condom rather. can she stop taking pill after finishing her 21 tablet.