(((((((Suthernsnail)))))))
I'm fading a bit... so this will be short...
Do read some of the material on vitamin B12.
And, if you have symptoms associated with low B12, get Methylcobalamin lozenges and dissolve them under your tongue, and keep notes for three weeks.
I would bet that you will find a significant improvement.
(But get the 5mg ones, because one of them a day for a month is about equal to a B12 shot a week.)