I've been having exactly the same rib pain. It started out on my right side just beneath the right rib. It was only on the right side for about 1 1/2 years. Then it spread to my left rib and lower back. I had an abdominal CT scan and Xray of lower back and they were both normal. Blood tests were normal. I've had this pain for about 2 years now. It seems to be consistent except it got worse when I was on Antibiotics in June for 30 days. It also got worse when I did an herbal cleanse (but only made it through 5 days of the cleanse before I discovered I had intestinal worms)... this was in January.
I did one month of physical therapy for the rib pain and I would say it made the rib pain slightly worse. My doctor wanted to send me for a nerve block and I said no to that. Right now I've started the olive leaf extract and garlic. I'm also having problems with recurring folliculitis that the doctor thinks is yeast and the antifungal shampoo seems to help that. I'm wondering if the entire problem with rib pain/back pain is actually fungal infection.