I got a copy of my lab work, and I'm confused because my B12 levels were never outside the abnormal range. They were on the lower end of the spectrum, but they were still within the normal range on the paper both times. My neurologist made it sound like the number was REALLY REALLY low the first time. Meanwhile, he told me that everything else looked normal, and yet there are six things that are marked either "Abn: L" or "Abn: H" on here. They're not THAT outside of the normal range, but they still are.
Anyway, my first B12 reading was 344, and my second reading was 483.