I slowly got more and more exhausted, unable to sleep after a while also. Then vertigo all the time. Many problems. I can't remember how low the B12 was but it was very low. Reg. doctors never checked it. Years later, an integrative MD did thank goodness. I got better, but then later, got Dysautonomia so I am four years into that healing with supplements, bio identical hormones and diet. More improvement is needed, but I have improved so much.