Have you just seen 1 neuro? Maybe see another one for a different opinion or approach? On the NC front my 1st one did not show but my 2nd about 6 months later did show PN. I had the NC/SSEP/EMG. The SSEP I guess shows more. Have you had any mri's of the brain and spine? Have you seen any other type doctors?
Is there a reason you don't want to try meds like Lyrica?