I pretty much have PN(idiopathic), started in the mid 90s with the weird 'wrinkle' feeling on the underside of the tips of my toes. Then, 6 years ago when making a dr. appointment to investigate what I thought was a foot bone spur, was when I noticed how extensive the numbness was, in both my feet.

Since then, I've suspected SFN, but have not pursued tx, as I don't believe the doctor's really care about these problems. When my [former] doc prescribed Gabapentin for the numbness in my feet, I knew that he:

1. wasn't paying attention to what I was saying, or
2. didn't really have a solution, but didn't want to admit it, so
3. was giving me Gabapentin as a placebo, so I would go away and
4. be thankful my condition wasn't worse, and not bother him with hard to diagnose conditions.

I hope you can find solutions, both for your SFN symptoms and the accompanying anxiety, which I too am plagued by, but for possibly different reasons.