Chronic Back Pain

Hi,

For the last two years I've had a significant yet dull pain in my lower back. It was bearable until about 6 months ago when, for no apparent reason I started getting 'pain attacks' that ranked had a pain score of 10. These attacks became more and more frequent until I was having them 3 or 4 times a week. Also, the pain in between these attacks has gone from a very manageable pain score of 3 to a constant pain score of 7 or 8. I haven't slept before 3am for 5 months now. About 4 months ago I started taking Codeine, which had mild effects for a while but then wore off. My doctor moved me onto tramadol which helps but doesn't get rid of the pain. Thankfully, I am now prescribed a sedative to help me with sleeping. Although inconvenient, I could deal with the pain.
However, in the eight last weeks I have gone from weighing 150pounds to 128pounds, and seem to be continuously losing weight. Also I'm developing numbness on the right side of my body. I've been to the hospital but have been thrown from department to department.

Any idea what the heck this is, or what to do about the increasing pain?

Thank you.