I haven't had to poop in maybe 3 days,i have some stomach cramps,could that be why?,i just recently got off my period about a week ago

Constipation redux: It is time to check your diet and water daily consumption to make sure there is plenty of fiber in it. The period has little to do with constipation in this case. Fiber increases bowel transport time and in addition to water bulks up the stool. Thus daily bowel movements are more common under those conditions.

Yes - could be: might be constipation, or irritable bowel or gynecological. If persists would see internist.