I started Phen on the same day as my TOM, it was a normal period. Well exactly two weeks after that one another one started. Then I went for two months with no period! Had my mind all messed up. Went to the OB/GYN and everything(I needed to go anyway). Before I found this forum, I couldnt find anything about period abnormality being a side effect of Phen....I was ready to kill my b/f...I thought he had given me something....or that I was pregnant (I have my tubes tied).