Without telling my whole story, I found out my B12 was 143 this past July 2017. I have been getting injections monthly since then (weekly for the first bit). I sometimes would feel very energetic but lately (the past month) I've been really tired and weak and my left arm is going numb and tingly again. By the way, my iron has been low forever too but I take supplements & folic acid as well. I have a long story of all my issues but I just want to know when my B12 will be normal again.