Hello to you too, and welcome to Neuro Talk. I know just a littlebit about PCS. Others will jump in too, with information and comfort.
Your youth will do alot to help you heal. Never say you won't completely recover. Many people do, and go on to lead normal lives.
I also understand about the no health insurance and the cost of the MRI. I had no health insurance when the ____T hit the fan for me. I went to the local hospital, and applied for some aid through my local hospital so I could receive the help I needed to find out what was wrong. Perhaps this would be an avenue to persue. Sometimes the local community hot line, has guidance on where to go, so you don't go broke trying to get well. Advocacy programs exist, but it takes some digging, and alot of work on your part with phone calls etc. Consider calling your congressman.
I can't tell you to have the MRI or not. I know how a big medical hit can set a person back, whos job is in danger. Also your doctor, may have some Idea of where to go for help. A second opinion would be worth the money to see if this MRI is truely needed.
I hope others will come by and give you some support and a few more ideas. Just believe too, that in time, you will heal and be OK. It is great that you are excersing. The PC job sounds good. I will pray that you can hang on to it. Take care of yourself. ginnie