I have had the B12 and Vit D tests and both are fine.

It seems about a couple of times a month, with spaces of 6-8 weeks inbetween episodes is when I feel like I am a zombie. I just don't feel right, spaced out, fuzzy, have trouble concentrating, getting words out etc and it just hits like 'bam' it doesn't build up, then after a few days it goes.

I don't have numbness, nothing is numb.

I think it was mentioned about eh skin punch biopsy but they decided that it wasn't necessary as my nerve conduction tests came back normal.

No I haven't been checked for gluten intolerance, will go and look at what the symptoms are.