Cramps /period

Allison
   I have always had god awful cramps during my period, but with in the past year I started to get random cramps thru out the month. I was told that it was ovulation, but that doesn't explain the other random cramps .
   I have had a cyst on my ovaries before, and don't know if that could be a cause for the cramps. I have been on birth control on and off but I have been traveling so much that I stopped taking it because it was causing me to have like three periods a month. But ever since I have been off it my periods last about four days . Is any of this normal ?