So irritated with AF

Kerri
AF is over a month late now, haven't seen her since July 27th. All pregnancy test are negative, even went to the doc last week and negative. Well AF was due again today, no sign of her. Doc said I need to wait until the end of October if I don't get AF by then, then I go to a obgyn. Doc thinks I'm just regulating even tho I had to normal periods in June and July