I finally went back to the GP after finishing loading doses nearly 5 weeks ago and not feeling any better. I've read all the stories in here about GPs not being very helpful, but still I feel a little amazed by my experience!
So I presented her with a list of my symptoms. To cut a long story short, apparently my dizziness, tiredness, shortness of breath, palpitations etc are all due to having anxiety and depression. Dizziness could also be because of dehydration, which apparently tall people are more likely to suffer from (?!) . My numb, cold, painful feet and toes are due to poor circulation.
I queried this, especially the shortness of breath and my numb/cold painful feet. I referred to the BNF guidelines regarding treating symptoms, not just going by the serum B12, but she told me my symptoms were not caused by the deficiency because I had had the loading doses. I asked about the enhanced treatment for neurological symptoms, was told they were not neurological but poor circulation and anxiety! She said they would only offer the extra injections if there were severe neurological symptoms such as you would expect with a serum B12 below 50 and I was nowhere near (mine was 154).
I am so glad I decided to self inject! OMG!