Hi @jwr, That is definitely a question a lot of us struggle with and I'm not sure there is a definitive answer but there are a lot of folks like us thinking I certainly hope so. Here's some information that I found that talks about it.

"What are the signs of nerve regeneration? — The pain is a sign of irritation of the nerve; tingling is a sign of regeneration; or more precisely, tingling indicates the presence of young axons, in the process of growing." — The Sign of "Tingling" in Lesions of the Peripheral Nerves: https://jamanetwork.com/journals/jamaneurology/article-abstract/570603

I've had idiopathic small fiber peripheral neuropathy for a little over 30 years and started taking supplements for it in 2016 and after a few months my numbness seemed to get a little better and the progression seems to have slowed or stopped but I haven't had any follow on nerve test to see if they are better that when I was diagnosed. The past few years my feet feel a little more normal and I feel some tingling but not a lot. So I often think about that question – are my nerves starting to heal a little. I also have balance issues and find it a little difficult to stand for very long. My personal thoughts are it has a little to do with my SFN but my old age also plays a part with degenerative arthritis. I've just never felt that it's worth it to have an EMG just to find out if it may be better than the previous one. I never had a skin punch biopsy and my thinking is they count the number of nerves so it would take a skin punch biopsy to see if there are more nerves (just my humble opinion).

There is an older similar discussion that you might find helpful to learn what others have shared.
--- Can Severe (electric shock-like) Pain be a sign of Regeneration?: https://connect.mayoclinic.org/discussion/can-severe-electric-shock-like-pain-be-a-sign-of-regeneration/