Welcome to Neuro talk. I know the last thing you probably want to do is see another doctor. I do recommend you see a good neurologist. Your PCP will give you a referral. There are so many different Neurological problems it is hard to pin point what this could be. Renards, can account for the cold hands etc. The lack of feeling in hands and numbness can be PN or carpel tunnel. See what I mean?
Just too many symptoms. Since your visions is being changed, I would think that for this alone, it would be worth a trip to the neurologist. I sure wish you all the best. Let me know what happens. You found a great site for support here. Keep in touch. ginnie

This sounds like something more serious than neuropathy, but I doubt anyone can help you with just knowing those symptoms. It sounds pretty scary, I would keep going to doctors until you pin point it better.

I mean you can start taking all the listed supplements found here, but I sure think you need a better diagnosis.

good luck

Ask your doctor about Autonomic Neuropathy, POTS, Dysautonomia. Hopefully they will know about them, if not find someone that does.