--is that your radiculopathy in the spine (radiculopathy refers to a subset of neuropathy that involves compression or compromise of nerve roots) is still involved, despite the operation. But your other situations may well be contributing to nerve pain now (hypothyroid, for example, is know to cause neuropathy, especially in narrow areas in which nerves have to pass through to extremities and are prone to compression, such as the carpal and tarsal tunnel areas).

The swelling may also be contributing; there is the "double crush hypothesis", in which multiple insults to nerve create symptoms that are more than the sum of their parts (you may have started with radiculopathy symptoms and now swelling, hypothyroid effects, etc., are exacerbating things).

You may also want to look at the Reflex Sympathetic Dystrophy/Complex Regional Pain Syndrome board here, which might be a possibility, given your surgical and other trauma:

http://neurotalk.psychcentral.com/forum21.html

I don't think any of the vitamins/supplements you've mentioned can hurt you in the doses mentioned; just make sure you take the B12 separately, apart from anything else, and apart from any food by a few hours, in order not to interfere with its absorption.