I had similar pains when I was driving, was put on pain killers by the Dr. Carried on when I left driving full time and got to the point where I was in constant pain from the waist down. Dr sent me to Physio which made it worse.
In the end I went to my local osteopathic clinic, best move I have ever made. His assessment was that the muscles for the lower 3 vertebra were pulling them backwards and trapping the nerve, been going there every 3 months for 7 years now and it the best its ever been. He has said that he can do no more, but every 3 months he loosens them off again. Costs me £140 a year, but can honestly say its the best money I spend