What are the reason for short muted time of year?

My period last long and was common heavy for yrs and for the second 3 yrs it became insubstantial and short.
Before it lasted for going on for 5 days, 2-3 days heavy and consequently light. Its color be dark red and brown.
For the second 3 years, it is bright red. I have it 1,5 days brawny and then a touch amount comes for 3 days more and then ends.What are the reason for short muted time of year?
Periods depending on the womanly will vary from 2 or 3 days to as much as 7 to 10 days. Mine be always 7 or 8.
They will also alter from light to extremely heavy. Mine begin at 13 passing huge clots and I have advanced endometriosis by 17.
So as females the one certain article is that we are all different and your menses will be specific to you.
check your hormones and check for PCOS and diabetis.