I am supposed to get my period this coming monday, may 9th, and wednesday may 4th, I got weird cramping in my lower abdomen, and aching in my butt cheeks. The next day I got a thick pink discharge in my underwear. (p.s. I have been on birth control for the past 3 years and this month switched to a higher dose. I was also late on a few pills, and I am very sexually active, with one guy.) What do you think this could be?