Preg after unwanted 72? Unwanted 72?

I had a medical abortion at 5 weeks on 2nd August. After that I didn't had my periods. I had unprotected sex on 9th Sept and after one hour I took unwanted 72. After that I continuously had pain in my pelvic area. I started bleeding on 25th Sept night. The bleeding was light red and very very slow compared to periods. Also the bleeding was very liquorish type. The bleeding continued for 48 hrs and then stopped. The pain is less than earlier but it is still present. I don't have tender breast. Was the bleeding my periods or implantation bleeding? recently I used to have periods of such duration but the flow used to be bright red and faster than this. I had preg test before bleeding and it was negative. Can I pregnant even after taking unwanted 72?