Menstrual problems:(

So I been bleeding 11 days now no change in the amount still heavy as crap I had a nasty blood clot yesterday looked dark as shit like black and stuff about the size of a quarter....so I brush it off and keep going well my stomach pain been bad for a while but it got worse, so I was taki ng a bath trying to relax in the tub bc I hurt real bad, well went to wash my hair got a bad stomache pain and blood came out my vagina quite a bit, I sat up n cryed idk what is going on can u guys please help!?:/