Synnove, I had that internal vibration feeling for a couple of months years ago--about 30 years ago. Like Debbie D, I have some cognitive problems and sometimes I don't get those old dates right, and I certainly am a goofus using "extra" programs on a main program like this forum. I did not yet have an MS dx when I got that internal vibration, so I was treating it with Choline capsules from the health store. I can say that these did work to alleviate the problem, and as long as I was on them, it was better. But the symptom went away, and I eventually stopped Choline.

I am used to treating some symptoms with supplements, because I also have Porphyria, which makes me unable to metabolize some drugs (not all, but probably the majority).
So Choline was suggested by some source as a way to deal with the internal vibrations, but I do not know who suggested it.

I too have vascular problems in the feet--I guess it could be called vasculitis, but the doctor just calls it Erythromelalgia. It comes from my other disease, Polycythemia Vera, in which I produce too many or badly formed red cells and platelets. These seem to crowd into the wee toes, where the vessels are small, and cause a pain in the nerves, so that my feet are the most painful part of me. However, right now I'm doing better with this, possibly because my red cells have stopped going up and also the platelets have stopped going up, even though they are around twice normal in number. My foot pain is way down. So I can do the housework and shopping without falling on the couch to rest too often.
I also have Porphyria, which is a disease in which the nerves are attacked by excess porphyrins in the blood, which happen due to a defective enzyme (very long story). So some of my neuropathy is due to that. I had just numbness when I had only Porph and MS, and now I have pain. But as I said, better today. 3 years ago I fell down stairs and broke my kneecap due to the numb feet on the stairs, so I watch VERY carefully where I put the feet.
I am on the Swank MS diet for about 28 years and I recommend it as a help to many of us, not to all, but many.