I have been having back and neck pain for about 5 months now. And for at least a year, have been experiencing different areas of joint or muscle pain for no apparent reason. Also have been getting headaches often. I have been to the doctor numerous times, and to a chiropractor, and nothing seems to get better. Is there a disorder or disease that would cause this kind of pain? I have been tested for arthritis, but I'm only 22 years old and seem to have a lot of pain.