If you are having neurologicallay symptoms, then I recommend you have you B12, homocysteine, MMA and B6 tested before taking more than just a simply multivitamin. Even with a very normal B12, you can still be functionally deficient in its neurologically active form, methylcobalamin which a rise in the homocysteine would suggest.

You can easily diagnose a B12 deficiency this way with the first 3 values, and if your B6 is high, it is possible you are deficient in its functional form, P5P which is absolutely necessary for so many processes in your body.