Most of my pain is on both sides. It's often all over (fibro) or joints on both sides at different times (lupus). I think you should bring up your MS concerns with your rheumy. He will probably refer you to a neurologist just to be sure. Mine has refered me to a neurologist on a couple of occasions. Mostly for severe brain fog and CNS issues. Last year I had brain MRI, EEG, nerve conduction studies and extensive cognitive testing. No signs of MS.
Prior to my lupus diagnosis I would get these spells (flares) where my legs buckled and I was in intense pain. I saw a neurologist who tested me for MS with brain, neck MRIs and a spinal tap. All was normal.
I think you should get checked for MS, just to be safe and ease your concerns. Love Ya, Donna