I have been having fairly regular periods 29 To 30 day cycles, mostly 30 day cycles. On a couple of occasions I have had periods on 32nd & 33 rd day. I'm 35 years old. Last month I had an early period on 26 th day, this month it is the 34th day & no period yet. We did not have intercourse, just foreplay with my husband in his tight underwear. I'm worried, pls advise