bleeding for over 3 weeks after stopping depo shot

i HAVE BEEN BLEEDING FOR 3 WEEKS NOW AND THE CRAMPING HAS WORSENED ..i WAS ON THE DEPO AND i DIDNT GET IT ON jAN 21 LIKE i WAS SUPPOSE TO iT STARTED LIGHT BUT NOW ITS LIKE A NORMAL PERIOD AND i AFRAID iM LOOSING TOO MUCH BLOOD ..LAST WEEK i WENT TO THE EMERGENCY ROON FOR TENSION HEADACHE AND HAVE BEEIN HAVING TEETH PAIN FOR THE PAST TWO MONTHS i DONT KNOW IF ITS RELATED BUT i NEED HELP