Bleeding after a miscarriage

I am confused whether my bleeding is istidah or posnatal. I had an eptopic pregnancy at 11 weeks. My treatment for eptopic pregnancy involved a D and C and an special injection to terminate the eptopic pregnancy. Since the treatment I have been on heavy bleeding for almost 5 weeks and now on my 6th week I am still getting brown discharge. My doctor said the bleeding lasted so long because of the injection and she also said that though this is not a postnatal bleeding, she recommended me to wait for 6 weeks until I start praying. Now that I am at the end of my sixth week, I am still having the brown discharge after the 5 week long heavy bleeding. Should I start praying or not? Please advise.