I recently just got off taking birth control which I was taking for 3 months. I skipped my period for all three of these months that I was on birth control. I just got my period and have been bleeding intensely for 7 days with insane cramps at night. Way beyond my normal period. Then today I passed a piece of lining that's about 2.5 inches long and 1 inch long. Is something wrong with me? What could cause me to bleed, cramp, and pass lining like this?