This can happen in some women. As long as the bleeding is not excessive (having to change feminie products every hour), you are fine. If the cramps become unbearable you may want to get checked for endometriosis.

i have a cyst on my left ovary. my doctor told me not to worry b/c it's small and it can come and go. i started having heavy periods, i was told heavy periods comes with large clots. and i also had cramps with that.
i found out i have d.u.b dysfunctional uterine bleeding from imbalance hormones.
you can get on the pill to keep you from having cysts on your ovaries, and it helps with cramps.