Stephgirl,
This is not fibromyalgia. According to the American College of Rheumatology, for a diagnosis of fibromyalgia, the patient has to have widespread pain in the muscles; on both sides of the body, and above and below the waist. So, if you divide the body into quadrants, then the patient has to have pain in all four quadrants. Also, the patient has to have tenderness in at least 11 out of 18 trigger points.
Unfortunately, there are several things that could be causing your discomfort. It could be coming from the hip joints, the SI joints, from the organs in the pelvic cavity, from the soft tissues around the hip joints, from the spine, etc.
Since it has been bothering you for so long, you should probably be seen by a rheumatologist or orthopedic surgeon for a thorough examination and maybe some screening labs and x-rays.
Good luck.