If you start having back pain you should immediately get off your feet, get in bed and give it a few days rest. If you do not you could easily injure it worse to the point of herniating a disc which can take months to heal and possibly require surgery. If you are someone with back problems here is a great source of information. It is on a back surgery site, but there is a huge amount of articles on preventing and curing back problems. Hopefully you can find something that will help. I haven't had the problem, but my wife has had back problems for years so we do know a lot about it due to  our research for finding relief for her.

www.herniateddiscbacksurgery.com