Provera is to be used for 21 days. You should take a second course of provera if bleeding does not stop. You seem to be having the symptoms of metrorrhagia(heavy periods). Various factors causing it are endometriosis,ectopic pregnancy,hormone imbalance,endometrial hyperplasia,polyps,use of IUD’s and depo shots, sexually transmitted diseases,PCOS and benign and malignant pathologies of the uterus.
I would suggest you to consult a gynecologist and get a pelvic examination and swab culture done to confirm the diagnosis. Treatment depends on the confirmation of diagnosis.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.