I would get that B12 checked. And make sure you get the numbers for the result. Should be over 400pg/ml.

Here is a video on B12 and how sneaky it can be and how doctors still to this day miss it:

http://www.youtube.com/watch?v=BvEiz...ature=youtu.be

The use of activated B12 called methylcobalamin is discussed on my long B12 thread, more in detail.
http://neurotalk.psychcentral.com/thread85103.html

Development in childhood of burning feet, may point to a hereditary type, which is not treatable at this time.

Also think back to any drugs used back then. Drugs can cause PN.
Dilantin for seizures is one. Some antibiotics also.

People can have the DNA mutation called MTHFR... which blocks activation of folic acid and B12 in food. People with this will show typical low B12 symptoms, but may test fairly normally.
For them doing a MMA test and/or a homocysteine level will reveal this problem. There is a DNA test now for it that is not too expensive, as well.

This is pretty common, 10-30% of Americans can have this DNA problem.