My period 28 day cycle last 3 days today is day 7 and stikk heavy bleeding with blood clots what's wrong?

Many possibilities: There could be a hormonal imbalance between estrogen/progesterone being made by your ovaries. You could have a polyp or fibroid, there could be pre-cancer cells causing this. Best is to see a gynecologist to be evaluated to make sure that it's nothing concerning to your health. An ultrasound and a biopsy of the uterus may be indicated. Bring with you a history of your bleeding patterns.