Two possibilities to mention:
1. If your skin is tender to touch and burning is not affected by body movements and different positions, then it can be shingles (Herpes zoster virus reactivation in one of the spinal nerves). Nausea can be also from shingles. This causes burning pain going like a stripe from the spine to the front. Often (but not always) rash appears after some time. Neurologist would tell you, if there is any available painkiler for your situation.
2. Bulging or herniated disc or some other disorder in your thoracic spine (osteoporosis, arthritis..) could cause pinched spinal nerve. This type of pain would be affected by different body positions and would not be tender to the slight touch. Again, neurologist could say more.
you need to come off everything and begin hcg and arimadex. I would use arimadex at 1/2mg 3 x wk and hcg at 250iu twice wk every wk and attempt to restore any natural test I could. The adex and hcg should help elevate sperm count and natural test over time. I would also use clomid at 100mg/ day for a couple wks and then drop to 50mg day for 2 more wks after you quit everything. Its going to take awhile, possibly a year before you are fertile again. Even on trt there is still a 50% chance of being fertile, but the choice to come off totally or stay on trt depends on how long you have been on trt up until now. If its been a year then Id attempt to drop everything, if its been longer then Id revert to a minimum trt dose of 80-100mg wk and continue on hcg arimadex regimen. U really need a fertility specialist though but for now this is what Id do personally