Has anyone used a TENS unit for PN?

I have had PN (not formally diagnosed) for years, beginning in my right big toe and progressing to include all of the toes. My main symptom has been "feet on fire," especially at night. When it got to the point where I couldn't sleep, I went to my PCP who prescribed amitriptyline. That worked great but I had to keep upping the dose. When it got to 30mg a night (which I know is still pretty low), I came to this forum and found a lot of people suggesting R-Alpha Lipoic Acid. I have been on that since last November and am just finishing weaning myself off the amitriptyline. Yeah! But here is the new development: I started using a TENS unit for overactive bladder (and I read that it can help with neuropathy). After about two weeks of using it 5 days a week, I am now feeling far more tingling in various points in my calves. It doesn't hurt; it is very mild and just strange feeling. Is it the TENS, which I stopped two days ago. Or could it be something else?
Has anyone successfully used a TENS unit for PN?
Thank you for any information.