Both. The way i see it is that brain and body are connected. In fibromyalgia, you have symptoms that come from both the body and the brain. Furthermore, they feed on each other causing escalation of symptom severity. This is the rationale behind multi-modal treatment: by helping both the body and the mind, you have the best chance of disrupting the feed-forward loop.
No. "all in your head" implies anxiety or neurosis or psychosomatic symptoms. The widespread pain may have a neurologic basis such as imbalance in brain chemicals. However, it is not the same as anxiety or depression. The key is weight control, exercise, and if necessary, medications to control the symptoms of fibromyalgia.
Baloney! ? fibromyalgia pain "all in my head". "Peripheral vs. central" is controversy. Academia bets elusive centralized brain functions causal. Despite peripheral pain aroused by motion & pressure, Neurologists deny peripheral neuropathy; even though painful trigger points shown anoxic, ischemic, & w. reactive substances. Pain-driven sleeplessness fosters depression & confusion misconstrued as "mental".