Cramps could mean your menstrual cycle is starting or it could be a deeper problem. This all depends on your past medical history. And a white discharge? Does it smell? As gross as this may be...a smelly discharge of any sort indicates an infection. Could be a yeast infection or a UTI...or worse. I suggest you see your gynecologist or family doctor ASAP.
Discharge can be normal. I think that's the most important thing they forgot to tell us in health class. If you pay attention you'll see your discharge changes cyclically throughout the month. If something changes or smells foul, it may be time to see a doctor. But not all discharge is bad. Some is required for the reproductive process.
White thin or slightly slimy might mean your ovulating. Lumpy? Yeast infection. Smell is a biggie- must be normal. If your period is due, and your cramps are on the side it could be that your prego, and your ligaments are stretching. You should prolly get checked out if none of this works.