I have been on a birth control for about three or four months now, but I am not taking it as a birth control. I am taking it because I have PCOS , and my periods are irregular, so I am on birth control to regulate my periods. I have been on different birth controls on and off for a few years. I missed had forgotten to take my pill friday night, and went out with my boyfriend saturday and we slept together saturday, didn t use anything. I got home very late saturday night/sunday morning (wasnt expecting to be out so late), and went to take my saturday night pill, then realized I had missed friday nights. I didn t think anything of it then because I have PCOS. (i know this doesnt make it impossible to get pregnant, but makes for very low chances) Anyway, I took my two pills that night, and have been right on track with them since. then yesterday, four days later, I started having break through bleeding . I have never had this happen to me. I am not supposed to start my period for another week and a half, so I know its not that. Then today I have been having very bad cramps . Even when im on my period, i hardly ever cramp, and when I do its only in my back. The cramps im having are in the back, and the front, and pretty decent. tehy have been coming in waves of being light then becoming stronger and then lighter again. They were the worst for a few hours earlier today, I am still having them but it is now just a dull achy pain. Also, the blood that is coming out is black. I plan on talking to my Dr. tomorrow but am looking for any ideas as to what could be going on.