Heavy bleeding with Mirena?

I have had my Mirena IUD for almost 7 months now. The first 3 months were a nightmare. I basically had heavy bleeding for 13 straight weeks. After that my bleeding stopped completely except some minor spotting around the time I should get my period. At that point I was completely in love with mirena. I was so glad I waited out the first 3 months. Well that love affair was short lived because after 3 months of happiness I have been heavily bleeding for 4.5 straight weeks again. Every time I think it's slowing down it comes back with a fury. Is there any way to make it stop? My doctor said it's all in place and there is nothing he can really do. I can't afford to keep buying pads and tampons constantly. Anyone else had this problem? My insurance won't cover the cost of removal unless it's medically needed and since my doctor says it's not I need other solutions.