That protein test was probably to check for monoclonal antibodies--rogue proteins that are often associated with blood disorders and which can cause neuropathy by interacting with nerve epitopes. (The best test for this is an immunofixation electrophoresis of serum and urine, but many neuros will only do a protein fixation test, which is not usually enough, as small spikes in gammaglobulins can go unnoticed in such a test--did you get copies of all the tests to see exactly which one it was?).

That TSH was absurdly high, and certainly hypothyroidism can lead to neuropathy. Your presentation was not quite "classic", though, and you may benefit from a bit more investigation, such as some more autoimmunity screening. (So much hypothyroidism is autoimmune in nature that it behooves someone with it to check out other autoimmune possibilites.) Many of us find the Liza Jane spreadsheets very helpful in this regard. They're accessible at www.lizajane.org, and they make excellent tracking agents for test results over time (they also help to suggest more obscure test to doctors who may not be familiar with them).

Now, as to nerve healing--it's one of the slowest bodily processes going, often taking years for even incomplete recovery, and along the way there are likely to be many starts, stops, back-ups, and strange sensations as the nerves regrow and reconnect to their targets (the process can be quite painful at times, as the brain learns to reinterpret signals). A diary can be helpful here, as it's hard to tell whether one is getting better except in long-term retrospect.