I get very similar symptoms. I had a CT scan this week to check my lower back for any signs of sciatica after CRPS spread to my lower legs. I had also considered/feared MS. A friend of mine at high school got it and I had similar symptoms. Wobbly legs, poor ballence, tremors, internal feeling of shaking, etc. but nothing showed n the CT scan at all. So it is clearly CRPS spread. I asked if these symptoms were normal on anouther forum and I was told that they were very normal in many people with CRPS. I guess because MS is also in the nervous system some of the symptoms are similar.
I hope this helps in some way.