What Causes Dark Clotting With Tiredness And Pain?

Hi,iv missed my period for 4 months been takin regurlar pregnancy tests. i started bleedin 4 weeks ago an had to take some meds to stop it for a week. now im off tabs and started clotting straight away. they are dark red mainly but with kidney like coloured clots comin out too? my body is extremely tired and in bit of pain. i have had heavy bleeds before but nothin like this,there is 0 smell to my blood either. on a period my blood smells tinny