Hi, I'd call your ob/gyn. That sounds pretty extreme to be honest. Things that could be happening include that you actually got pregnant and are having a miscarriage situation? That you have an ovarian cyst that is passing (I did this and it felt like the worlds bloodiest, worst period ever). You could have a fibroid (I'd guess this one of the three). I would definitely call today to be seen by your doctor and they should work you in quickly. Any heavy bleeding over 7 days needs evaluation. Let us know what happens, okay?
Also, take iron and vitamin C. Get the most easily absorbed kind of iron (it will say on the bottle) and take it with the vitamin C every other day.