Nothing to worry about... You may and probably will, not being negative here experience all sorts of crazy unusual sensations, pulsing, shimmering, vibrating, hot n cold to boiling hot and freezing, to numbness, shooting pains, aching, noring aches that become painful, anywhere and everywhere, sometimes in one or two limbs, or simply islolated in one spot, to sometimes full body episodes...Even Swelling of limbs, and oh the stiffness anywhere in the body.
Hot pain, and cold pain. Flare ups that get out of control to more manageable days. Pacing yourself can help sometimes, other days nothing will help.
Stress and Anxiety is a biggy... Even over doing it visually can set the brain off the same as 'simply thinking to stressfull worrying'... It can trigger the brain to work against your body and all those wierd pains, aches, sensations, swelling, stiffness, to shimmering, and flu like symptoms AND the fatigue. Have I left anything out..??? lol... The key is to just let your body be. Take the changing or manifesting of all those different physical aspects and learn to go with the flow, and manage as best you can. Get to know your body this way... It's like getting to know a new friend. Don't argue with it, you can at times release the valve and yell and swear at it sometimes.. hahaha... But all in all, it's a myrid of different and complex ball of Skewed up Brain messages to area's of the body.
It's not lethal, it's not fatal... It's just an annoying friend that can disrupt life and you learn to adapt to it's challenges... Accept your limitations when they happen daily, weekly, Yearly.. and learn not to abuse the 'Remission Days, weeks, months, Hour/s'... I'm am lucky to get anything from an hour to 5 hours remission in 6 - 8 months. But I'm a fully compromised case from head to toe after a serious MVA (car accident).... 17 yrs with this 'Friend, Fibro'.. Loathed it with a passion, but learnt to befriend it... Life is what you make it... with the ups and downs of it...
Key advice 'Don't read to much into your symptoms, and stress over it.. it's nothing to worry about...just learn to befriend it and work with it as best you can and know your not the only one, you have many Fibro buddies! :-)) (fellow sufferers)...