Hi,
I had something similiar, though my pain level wasn't quite that high. I ended treatments near the end of March, 2013 and noticed the pains towards the beginning of May. They started on one side of my upper back, stayed there for a while and then 'traveled' its way across the middle and then to the other side. I had a slight case of shingles a few years back and that is what I thought of immediately; no rash ever developed though and after a few weeks (2-4?) it has gone away. I was still taking liquid Roxicet for throat pain and that was enough to relieve the pain, but not fully take away the sensation. I had mentioned it to a few doctors and got that puzzled look like they thought it was in my head. Whatever it was has passed now without any residual effect (I hope).
Best to you,