Before I continue further with FMS I feel I opened a can of worms with adding MPS and CFS therefor I will explain in short detail why they would be mentioned. Many times all 3 of these conditions will either live together co-existingly, or one may be diagnosed with one where infact they have the other.
MPS known as Myofascial Pain Syndrome. Myofascia is a thin film that wraps itself around the muscle tissue, holding all of the other parts together. Hence giving it shape and supporting all of the body's musculature system. With MPS or FMS there is a thickening and tightening of the myofascial and for those who have both FMS and MPS; they will have double the trouble. Person's with MPS may also experience pain in the jaws and have unidentifiable problems with their teeth; great pain but no explanation why. There is much more on this syndrome which one of my links will take you too.
CFS; otherwise named Chronic Fatigue Syndrome are also very similar to the symptoms of FMS . It has been noted that those suffering FMS may feel more pain than one with CFS; those with CFS no matter how much rest or sleep they may obtain can never feel rested. Persons with CFS are also noted to suffer more from the cognitive dysfunction. Those with FMS suffer from it as well but perhaps not to the same intensity. There are again here many other details to CFS to those I may have confused which will be included in many links to FMS as where you find one mentioned hence follows the other as the 3 our very similar.(One may note related).
Upon your original diagnosis you will most likely be given something similar to an oral exam, and then the doctor will proceed with his touch point triggers. You must fit a certain amount of trigger points and have had the pain regualarly for a minimal of 3 months for a proper diagnosis. Below is an image that will show where these common trigger points lie.