I have dizziness, headache, and breathing difficulty. Can vitamin B12 deficiency cause this?

Hello doctor,

I got symptoms of an anxiety attack, fatigue, and exhaustion after my periods. I was very tired, and could not walk properly. I was walking in a zig-zag manner and had balance problems. I used to wake up with a numb arm in the morning, and I was having insomnia and tingling in my arms, fingers, and legs. My family doctor diagnosed these with vitamin B12 deficiency without even testing. But after about ten injections, my symptoms improved, my numbness, tingling, walking problem, and muscle weakness improved. All pains went away, and my sleep came back.

After a few days, I again got muscle fatigue, low BP and weakness, confusion, rapid heartbeat, and anxiety symptoms. I again took a B12 injection, but a day after that injection, I felt worse, with dizziness, shortness of breath, exhaustion, headaches, mental confusion, chest pain, and choking. Then I thought of doing iron tests since I was anemic in childhood, so I thought these symptoms could be low iron.

I did CBC, iron profile, ferritin test. My Hb was normal at 12.4. MCV, MCH, MCHC were low. Serum iron 29, transferrin saturation was 9%, and ferritin 33. So, I again went to a family doctor who gave iron tablets for only ten days. My symptoms improved in two to three weeks. He gave ferrous ascorbate 100 mg. The only symptom that improved were heart palpitations and exhaustion. I could not get up from bed for one week. But after two weeks, my energy improved. Right now, it has been six weeks, I am still taking 150 mg iron tablets, and I still have all those symptoms, but only the frequency of the symptoms has decreased.

I still get chest pain, breathing difficulties if I overexert. After walking for more than five minutes, I still get dizziness, headaches, and slight left side chest pain after a long duration of mental work. Now, I want to know for how many more weeks or months should I take iron tablets? And I felt worse after my last B12 injection. Since then, I have not taken an injection. Do I need to take more b12 injections? As I have already taken B12 injections, but I never got headaches, shortness of breath, dizziness in B12 deficiency. These things I got a day after my last B12 injection. Since then, I am afraid to take more b12 injections. I do not know what to do?