What Causes Heavy Periods And Cramps Post Child Delivery?

I m having excessive spotting since the birth of my son last year (july). After 6 weeks post c-section I started having very heavy periods, again. I know i have a cyst on my right ovary, but my gyno says having it removed wont change my periods. I m bleeding 3-4 weeks out of every month. With no idea as to whether it ll be heavy, light, just spotting or what. This month (month 4 of a low estrogen bc) my period was entirely dark brown, and coffee looking. I m taking DIM supplements, avoiding caffiene, taking red raspberry supplements, drinking the teas. I m taking ibuprofen and tylenol and still in a lot of pain and discomfort. What can I do? I am miserable... out of 56 weeks i ve had only 12 weeks of not bleeding... he has not run any tests other than blood sugar, and it was slightly elivated for the first time in 15 years. Normally my blood sugar is midline normal range. I m anemic though I take supplements and eat beef. I exercise when I can, but nothing I do is helping.