I have had numerous nerve blocks and they were all the complete opposite of what describe below. I think your biggest concern needs to be the fact that the doctor is not using an x-ray / CT machine monitor where he/she is placing the needle. If the doctor hits the wrong spot you could end up paralyzed or have bladder incontinence.
Also, your blood pressure needs to be monitored because it is a very painful procedure and this could cause you to have difficulty breathing. I was partially sedated every nerve block I had done, and I thought it still hurt like hell. The second one I had done, went really bad because they did not give me enough of the sedative and I had difficulty breathing. After that experience the doctor finally got the medicine dose right.
I think you need to find a better doctor as he doesn’t sound professional and also sounds like the doctor is taking a lot of unnecessary risks with you and your treatment. As for cost, I think each nerve block treatment was around $300.00. Good luck with everything and keep me posted. I know it maybe difficult to switch doctors but I would start with telling your current doctor all your concerns. If no resolution is met than ask him to refer you to someone else.