This won't make you laugh, but it could bring the smile back to your face.
There is a brilliant book called 'Treat your own back' by Robin McKenzie, ISBN 0-9597746-6-1
If you go through the book, cover to cover, it will explain the nature of many back injuries, and more importantly, tell you how to stop the hurting.
Buy it, it's superb. It's available from WH Smiths here in merrie england.
John (long term sufferer of back problems, now almost sorted)