I know how you feel. I went to pt for my back a few months ago. I had pain in muscles that i did not know I had. I lay in bed and play games on my tablet. I have noticed just using my right hand to play, my arm muscles start hurting after 10 minutes. It does not take long to overwork our muscles. I now put a pillow under my arm and it seems to help.

Muscle fatigue & pain is associated w/FMS. Driving, as you indicated, is an issue. It's necessary to keep changing & adjusting position - even the seatbelt becomes uncomfortable. Some days are worse than others. I also have ME/CFS which causes muscle pain & weakness after physical activity - even just walking & moderate hiking. It is called "post-exertional malaise". I can be very active one moment & pay for it later. Lately I have been actively involved in photography which I love but it comes at a price. I cannot stop doing things that make me who I am. Life for me has been very challenging ever since I was a very young child with chronic health problems. I wish you well🌷

I know exactly what you mean, it's like having lactic acid in your legs after running (I vaguely remember running at school 😆) I get it in my arms holding the phone to my ear or brushing my teeth. I know the research doesn't show it but it feels like my muscles are giving up. I feel weaker every day. X

when i walk up my stairs sometimes the leg muscles in my calves feel like they have torn in half, sometimes i put my hair up because my arms wont work long enough to straighten my hair

Yes. My bedsheets feel like Velcro. Today I was holding a plant when I shut the car door so I nudged it with the top of my arm. It felt like I'd been punched and it hurt for about half an hour