Take a look at the symptoms I had when B12 deficient. I had many of the same symptoms, and it took 3-5 years and 8 specialists before one thought to test my B12 level, and thankfully he was one of the few who realized low "normal" B12 levels can cause problems.
http://jccglutenfree.googlepages.com...ciencysymptoms

Here are a couple of good articles:
eMedicine link on vitamin B12 associated neurological diseases:

AAFP on Vitamin B12 Deficiency

Hope this helps!

Cara