Hello all. I'm a 30 year old male living in the US. Five months ago, I zeroed in on B-12 deficiency as the most likely culprit of my four years of slowly worsening symptoms. The symptoms seemed to match up better than anything else I'd researched, and I know that my great-grandfather had PA starting about the same age (and possibly his mother, but it was before they knew what B-12 was and she died at age 42). My symptoms are (in rough order of presentation chronologically): shortness of breath, chest pain, dizziness / unsteadiness when moving, joint popping / pain, muscle soreness / frequent pulling, headaches, brief moments of utter confusion, paresthesia, muscle spasms, lack of energy, require 8 - 10 hours of sleep, palpitations, tremors (particularly when drowsy), and vision problems.
So I started taking daily oral B-12 tablets as soon as I could, and for about a month, my symptoms steadily improved (especially shortness of breath and muscle soreness). But since that time, my recovery seems to have stagnated. I've also tried augmenting the tablets with cyanocobalamin self-injections weekly and folic acid daily, but I still feel stuck. I've tried going off the oral tablets a couple times and the worst of the symptoms come rushing back within a few days.
I did go to see a doctor about the B-12 a couple times, but--as I'm sure comes as no surprise--he seemed to know almost nothing about it. After I tried to carefully school him, I was only able to get a serum and IF test done and a prescription for the injectable. Unfortunately, the serum was taken after I started the oral tablets, and the 1200 result didn't seem to mean much. The Intrinsic Factor was negative.
My thought now is that maybe I don't have B-12 deficiency or that alone. My symptoms, family history, and response to additional B-12 would seem to corroborate it, but the test results and stagnated recovery don't.
So my questions to the community are:
Does it sound as though I have B-12 deficiency?
What tests should I insist on to find out if I do have B-12 deficiency?
If not B-12 or B-12 alone, what other conditions could it also be?
Also, I'd like to offer a $500 bounty / gift for critical information leading to my recovery. Thank you greatly for reading all this and for your input.