I've Been Bleeding For Two Months Now. I Have Been

I've been bleeding for two months now. I have been on depo provera for a long time. This has been a strange type of bleeding aside from the long time period. I started "bleeding" brownish reddish residue. That later turned into black. Then back to brown. Vice Versa. And For the past week have been bleeding red with dark blackish reddish clumps. I have not stopped bleeding for more than 3 hours straight. What is wrong with my body? I am only 16