Uggghhh! RM, I totally feel your pain! I wouldn't wish back pain on my worst enemy.
I'm still recovering from hurting my back New Year's Day....slowly it's getting better and I'm able to race & stuff. But still, it's a touchy thing....any little hint of real pain and I have to back off, which is frustrating when I'm feeling so strong right now. I haven't been able to do any hill training this year, though, because of the pressure climbing puts on my lower spine. I'm still seeing the chiropractor, but now I'm down to once every two weeks (doc says that if I wasn't active, it would be once a month now, but oh well).
Have you tried ice instead of heat? One of the first things I did wrong with my back injury was to apply heat, which only caused the area to inflame more, hence more pain. The instant I applied the ice, it was unbelieveable relief. Ice packs and me have been on intimate terms for months....
Take care & hope you get to feeling better soon (back pain sucks!)
~BikeMomma
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." --Albert Einstein