Gretall
My mom has Lupus and your symptoms sound like hers

have your been tested for Lupus? I get these MS Hugs and I was describing it to my mother and she says she gets those too, she has alot of pain all over her body, she also has Fibromyalgia.
I think any disease of the immune system, you will have a host of symptoms that mimic other diseases, my neuro said that it is common or should I say not rare for one person in a family to have an auto immune disease and another member gets one too.
It's easy to say don't stress. but the stress is probably making you feel crummier, do research on auto immune diseases and MS, and Lupus and become knowledgeable that way you won't be so scared.
Let us know what happens