Cellcept induced muscle strains/problems

I started CellCept the end of August, 2024. I write this on 4/9/25 to give you a frame of reference, so I've been on it just short of 9 months. My shoulders and arms were affected from the beginning of my MG (8/1/15), but it seems now I am having issues with my rotator cuffs in both arms. I haven't really done anything "out of the ordinary" to cause injury. I first noticed my left shoulder one morning when I leaned down to tie my shoes. A sharp pain and cramp radiated from my shoulder through my bicep. I saw an ortho and x-ray was negative for any tears. I'm now having the same feeling in my right arm, but to a much lesser degree. I've been on Mestinon from day 1 and continue it at a smaller dose (60 mg 2x a day) with the CellCept. Has anyone else experienced any muscle pain issues? My energy level is pretty good so I'm thinking of reducing or eliminating the Mestinon. I have asked my neuro and he doesn't believe there is any correlation. I've not had any issues, other than leg cramps, on Mestinon only.