What Causes Heavy And Prolonged Vaginal Bleeding With Large Clots?

I took My Way emergency contraceptive in November. Week later period started like normal. Also at that time began Gildess 1.5/30 (21 blister pack). Since then I've had severely heavy non-stop bleeding and large blood clots (going on third week). I'm at wits end. Took self off pills will that likely cause bleeding to cease?