First you need to confirm it's a miscarriage
or not. In case of miscarriage passing of blood clots
& accompanying cramps usually last for 3-4 days.. If it is continuing beyond this period (as in your case) then you need to visit your gynecologist & get examined as some amount of product of conception might still there in uterus
..gynecologist will examine & take necessary step (usually they do D&C method)..retained product of conception might lead to infection which explains your other symptoms..thus visit your gynecologist asap..
thanks for query..take care..bye..