serum zinc and serum magnesium tests could be a good idea. they're involved in a wide variety of disease states including ms and fibro.
the results would likely come back 'normal' - if you do get these tested, disregard the 'normal range' and ensure you get the specific results, including the units. 'healthy' values are available, details in the first post of my ms nutrition topic in the 'regimens' section here at TiMS.
The relationship between serum trace element levels and clinical parameters in patients with fibromyalgia (2008)http://www.ncbi.nlm.nih.gov/pubmed/18496697
We examined the association between serum trace elements and clinical findings such as number of sensitive tender points, severity of fatigue and functional status in patients with fibromyalgia (FM). ... The demographic data, disease duration, number of tender points and accompanying symptoms (fatigue, sleep disorders, headache, paresthesia, irritable bowel syndrome, sicca symptoms, Raynaud's phenomena) of the patients were noted. ... Serum levels of zinc (P = 0.001) and magnesium (P = 0.002) were significantly decreased by FM groups
, whereas there was no considerable difference with selenium levels of both groups (P > 0.05). Association between serum zinc level and number of tender points (P = 0.008) and that between fatigue and magnesium level (P = 0.003) was found as meaningful. According to the results of this study, it was asserted that serum magnesium and zinc levels may play an important role in the pathophysiology of FM.