Should I worry?

So about 2 months ago I got the Mirena IUD. Prior to it, I had zero issues with cramping, excessive bleeding or pain. Two months later, and the bleeding still hasn't stopped (even with my daily doses of estrogen). I've also gotten horrific (lay down- can't move) cramps during my normal period timeframe. But my biggest concern is the constant burning feeling I've been feeling in my left ovary. My doctors had an ultrasound done and the IUD is properly placed, but I do have cysts in my ovaries. I don't know if this is causing the pain or if it's something else I should be concerned about. I've also had chunks of endometrial tissue come out, which is freaking me out.  The doctors haven't been concerned and keep say wait until the three month mark, but I don't want to hurt my body in the waiting process. Advice/Experience please!