Why has my bulging disc left me almost completely immobile?

Pain, spasm: Please get evaluated by a spine specialist. A "bulging" disc should not completely immobilize you. There may be spinal pathology present that only a specialist may diagnose. Is the disc really bulging, or is it herniated, degenerated, part of an instability, etc....?

Muscle weakness?: A disc bulge can cause weakness, numbness and pain, or a combination of those three. The disc causes these symptoms by pressing on a nerve that travels down your leg. It can be very painful and disabling. If so, seek treatment from a spine surgeon. You may need medication, injection, and possibly surgery if these don't work. If you experience weakness, loss of bowel/bladder control go to er.