What Causes Pelvic And Abdomen Pain After A Miscarriage?

Hi, I had a miscarriage 2 weeks ago and I have seen a doctor that prescribed me some pills. I took the pills and I eliminate the fetus. I have been back to the doctor after one week from taking those pills because I still had pelvic pain on the lower abdomen. I was prescribed doxycycline for one week in case I had an infection. I took the antibiotic but I still feel pain on pain on the both ovary. Do you have any advise for me? Why I still have pain on the ovary? At this time I take ibuprofen so I can handle the pain.