I certainly am not an authority on B12, but I was B12 deficient too, and celiac. Has your ferritin been tested again? 3 is way too low, they say to aim for 50, and I thought mine is low at 26.
B12 at 216 is too low, 163 is definitely too low. I take 5000mcg of B12 now, was on 3000mcg when I was tested in July, and my level came back at 1015. Are you still doing the shots? I am positive we will have to take B12 for the rest of our lives just to keep the level steady.