Back Pain

Okay world, I need some advice. I have a back spasm that has been in pretty much an acute state for 2 weeks now. I'm in extraordinary pain. Physical therapy can't do much because the pain won't let me do the exercises. They are doing an MRI next week. Major pain killers and muscle relaxers don't help. The only thing that seems to is lying on the floor with my legs up on a chair. Anyone have any tips?