i had sex in oct. of this year that month i got my period but it was on the 30th day. my period is never regular it either comes anywhere from the 26th day to the 30th day the next month i got it and it was on the 26th day and this month i got it and it was on the 27th day....do i have anything to worry about bc it was on the 30th day after i had sex?? please help thanks