You can go to your neurologist and have them test your large fiber nerves if that shows nothing insist that they do the skin biopsy for Small Fiber Neuropathy. One of them I can almost guarantee will show that you have specific Neuropathy. From there have your Dr refer you to a hemotologist for signs of any blood or bone disorders once they look at your test they can determine if you are to be treated by them or by a endocrinologist, a rheumatologist, your regular Dr or by your neurologist. You will need many different specialist to see what is the cause.

I would think you could get better relief, if you get on the right medication. From what you've said, I have similar neuropathy in the same areas as you. After a long drawn out process of discovery, when I started on taking amitriptyline I began to get relief. The process always starts with a small dose to see if tolerated well. I started that way and the dose was increased until I got substantial relief. I'm taking it now and have for years. Other medications were tried first and they did nothing for me - so I would say, I think you could be doing better if you get the right medication.