What Causes Pain In Lower Back Having Diagnosed With Bulging Disc?

I have been suffering from mid and low back pain. Recently an MRI revealed bulging discs and arthritis. I'm taking Nabumetone, and I have had two recent treatments on a decompression table. However, my concern is that I have some serious rib pain on my left side, out of no where. I hope it is a strain, but with my discomfort lately, I'm getting stressed at this ailment.