@darina, I forgot to mention another discussion where you might find other members with similar symptoms:
--- Vitamin B12 deficiency and small fiber neuropathy: https://connect.mayoclinic.org/discussion/vitamin-b12-deficiency-and-small-fiber-neuropathy/

As far as postponing a treatment that may provide some relief for your pain, that's a question to discuss with your primary care doctor. If it were me and the treatment was covered by insurance, I would probably give it a try to see if it made a difference since I think the treatment involves a series of appointments and you may find relief early in the treatments. If not, I'm guessing you can stop going. You might find the post by @duquer on his experience with Sanexas (EcST treatment) helpful - https://connect.mayoclinic.org/comment/701008/.