What Causes Menstruation With Heavy Bleeding And Pain?

My periods are usually very regular, not too heavy and last around 4 days. My past three periods have been excessively painful and have caused me extreme fatigue (much different than my normal baseline). I am currently on my period that started March 21st. For the first few days it seemed normal (with the added symptoms), however after 7 days my period suddenly became much more intense. I seemed to be losing a much larger amount of blood (about 6 tampons in 10 hours) and my pain has been much worse. I am still on my period and don't know what I should do from here. Does this sound like a common menstrual problem?