Aunt Flo... THAT BIA!!!!?

does anyone else ever feel like af F's with you? before i started ttc, i could predict my period almost down to the hour. always on time, always the same. since ive started ttc... i can never tell when af is going to show up. this month for example, she was late.. by a few days, which in turn gets my hopes WAY up because she was so consistent before. i always feel like she's f-ing with me... like you see on the commercials.. you know the one... the little lady in the pink outfit with your "monthly gift." its so annoying. anyone else feel this way?