What Causes Contractions And Bleeding After IUD Removal?

I am 48 years old and had a mirena IUD till a couple of years ago and various ones over 19 years. I never had cramps or heavy periods, except for the first one at around 12/13 years old and they usually last 3-5 days. I have two kids and have had 3 abortions and miscarried once. I have 2 known fiboids on the utirine wall for years now. Very painful at times but no heavy bleeding. Before I removed the IUD I had a heavy pain in the lower abdomen, thicker uterine wall and lighter periods. Since I removed it I have been fine but lately I have menstral cramping and during this last period after a week of moderate/light bleeding I started getting contraction like pain followed by bleeding which lasted another 9-10 days. I am very fit at 126lbs @5"7" (23% body fat), run 5 days a week for 30+ minutes. I do suffer from migraines (since 11 years), mild glaucoma, high good and bad cholesteral (not on meds), minute calcifications in the breast, very low blood pressure usually 90's/50's but sometimes falls lower and I can't stay awake. Pulse in upper 50's- low 60's and gout. More recently I have developed digestive disruption and lack of tolerance for bread/yeast, starchy products. Often I feel nausiated and need to sit or lie down. Sometimes I have a lot of stress but most of the time it is under control. What is with the contractions and bleeding?