When having my menstruationperiod I bleed heavy 2-3 days, have sever pain and horrible cramps, 40year old, getting worse the older I get, what's wrong?

Several choices. Heavy and painful periods can be caused by fibroids or adenomyosis. The first step is to be examined. The second would normally be to try birth control pills. Other treatment options can include mirena, (levonorgestrel) Lupron or surgery.