I had to go get IV Chelation (EDTA + DMPS) for 2-3 months to overcome what it sounds like you've got, every bone in my body hurt, I couldn't walk without limping, the burning, everything and much more you are not mentioning, and I certainly could not run. Previous to the incident I was very healthy and did lots of running. The IV Chelation has helped enormously, but it wasn't overnight. Sounds like you are very posioned like I was.

I am real sure that without the IV chelation I would still be suffering, and possibly worse, possibly dead. You might consider doing as I did and locate an integrative med DR that will do the IV, only heavy duty direct cleaning of your blood will help if it's anything like I experienced, which was hell.

I am better now, can run again, but it took a few months. You might also consider a colonic or 2 or 3, if you ingested mercury it's in your stomach/colon, and spreading from there. A colonic or 2 will flush it out quickly.