I have a period every 20 days,most of the time severe cramps accompany it.The cramps get so bad I have to curl up in fetal position to ease the pain.

There are many over-the-counter drugs NSAIDs (help for menstrual cramping) -- (ibupofen and naproxen), and acetaminophen that may provide relief. A heating pad works well for cramps when used OTC pain meds. Some women benefit from exercise, some from rest. There are also prescription drugs to help alleviate this painful disorder. Talk to your health care provider about them. Before you diagnose yourself, see your health care provider to be sure the pain you are having is not associated with another condition like PID (pelvic inflammatory disease), endometriosis, or any other medical conditions.

Your cycle is not unusual in that it varies with most women from 2l to 45 day periods. The length shortens as you get older.