What Causes Clotting Of Blood During Menstruation?

I had a therapeutic termination on june 27th and had the typical 2weeks of bleeding then some spotting the following few days. The july 18 I had a non hormonal iud placed since then I have been bleeding and clotting. Today I have had almost gushing from me and quite a few decent sized clots come out. What should I do the doctor I went to today took my blood pressure thats it said in a week go to the hospital