There is a drug that the GP can prescribe for heavy bleeding. I had very heavy painful periods for years, it was The Pill that eased symptoms.
I used to lay on a large bath towel in the night, plus two thick pads at once and two pairs of knickers. The towel had to be above my waist as the blood seemed to leak upwards somehow ....... If I stood up I would pass clots. Awful. Embarrassing. In the bath clots would leave my body so DH used the water first. Then I could clear up.
Let us know how you get on?