I have regular periods,it comes earlyer every month by 1 day, for example,feb 18 my period came and now march needs to come 1 day earlyer so the 17. And I havent got it so I was wondering if the month of feb sense it has 28 days does that mean it will come to days late for this month of March?? I am 20 years old,and I am having unprotected intercorse?? YYYY@YYYY