I also had a hell of a time convincing doctors that i had real problems, i went to 6 GP's none of them had a clue, one rheumie, that couldn't find anything wrong and one Professor of Neurology, who done a Nerve Conduction test and said, " i showed no signs of PN,[ nerve conduction only tests for large nerve damage] another idiot that actually said to me " i don't think you have burning feet, the test [NC test] proves that , it was the Internet that helped me find out what was wrong, in particular the PN forum i stumbled across in my desperate search for answers, the experts here pointed me in the right direction, thank god, so i insisted that my local GP send me to a PN expert which i eventually got to see [ after a battle with him ]and he diagnosed "Prediabetes" as the cause after a 3 hour Glucose tolerance test,
& i was running real low on B12 as well.
The reason why your feet are burning is that the small nerve's are damaged and are sending confused signals, your small nerve job is to sense heat, cold & pain, a clear indiction was when you felt that neuro's tool feel differant above your knee, he should have picked that up and sent you for a QS test.
I have to get going , pretty busy day today, but others will explain more.
Brian