After 8 months of back pain, a lot of doctor visits, and a ton of tears, I have an answer. I had an MRI on Monday and received the results yesterday. The disk at L4/5 has a large herniation. I am being referred to neurosurgery.
Of all the things I was thinking it could be, this is the one I wanted the least. I know several people with bulging disks and they have had problems their whole lives.
I cried for a bit, but then I decided that I'm not going to let this get me down. My goals now are to lose weight and quit smoking.
Thank you to everyone for your kind words in my newbie post! Looks like I'll be staying awhile...