1. Go to the doctor! At least give them a call and speak to someone about what it might be, but they might want to see you anyways.
2. If you think the discomfort is from stopping the pill, many women have "regulated" themselves by using a supplement called Vitex (Chaste Berry). It is supposed to help get the reproductive system back to a normal level of functioning after being used to extra hormones. Many fertility experts recommend this to women who want to get pregnant after being on the pill for a long time because it helps get the cycle regular again. It might help with other issues like tenderness, as long as it isn't due to some other issue.