The fetal sleeping posture is similar to that of the fetus in the womb, which is curled up. When you sleep in this position, the muscles surrounding your abdomen relax, providing you with a much-needed respite from period cramps. It also decreases the possibility of leaking, even with a high flow rate.
Use a heating pad and Tylenol as well. Never, ever, ever exceed the prescribed dosage on the bottle. When taken incorrectly, Tylenol may be pretty deadly.