My girlfriend and I engaged in unprotected sex less then a week after she got off her period. To be safe we went to planned parenthood and she received and took Plan B which is a "morning after" pill. About a week after taking it she got another period which lasted about a week. Today (two weeks from when she finished the period just mentioned), she got her period again. What does this all mean? Is it due to the Plan B pill or should we be worried about something else?