Go to a rheumatologist. I was diagnosed with Hashimoto's in 1995. In 2006 started having muscle pain and headaches, finally after a ton of doctors and specialists they diagnosed me with fibromyalgia. The years go on, I'm getting worse and have more symptoms, BAD FATIGUE among other things. The rheumatologist finds out I have rheumatoid arthritis too! Now, I start coming down with this red rash on my face and white patches on my hands, feet, legs and arms (I'm Caucasian) so I decide I need a second opinion from another rheumatologist, well he confirms the fibromyalgia, rheumatoid arthritis and after we get the blood work back, possibly Lupus! In addition the thyroid disease. My brother has Lupus and it can be genetic. The doc says all these autoimmune diseases can run parallel, not unusual! My suggestion is have blood work done by a rheumatologist and make sure you tell him/her ALL your symptoms!! Good luck!
I also confirm all of this through the Mayo clinic, which I go to for an appointment, best medical facility ever!!!