At that level, it would be expected to start a course of B12 injections.
And to test for Pernicious Anaemia.
The effects of insufficient B12 are far worse than some jitters. (Maybe I've been lucky, but I've never felt in the least jittery from B12.) And several of those effects are result in permanent damage.
Probably the most common form for personal supplementation is methylcobalamin. But don't get hung up on this issue. Get tested and treated adequately.
Is there any other reason for low B12 such as being a vegan?
Suggest you have a look at the Pernicious Anaemia Society forum:
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