Welcome Kiwigirl,
You'll find a wealth of information about B12 here, and hope. One thing you can do to help yourself is get some methylcobalamin (1-5mg) and take it daily on an empty stomach.
As you read more here, and others contribute to this thread, you'll get a better idea of other tests & things to ask your doctor about.
Doc
PS Check for info on B12 and other supplements in the
Peripheral Neuropathy Forum and
PN Tips, Resources, Supplements & Other Treatments Sub-Forum.