I m 21 years old, female, have been on birth control pill for years, same kind, I recently changed my diet and exercise and a few days ago I noticed some spotting, I m still on the active pill and shouldn t get my cycle till next Tuesday, it has gotten consistently heavier to the point it s pretty much a full blown period. I took a pregnancy test and it was negative, we also used a comdom. What s wrong with my uterus? And I why am I in pain and on my period when I shouldn t be?