Maybe get your liver checked? I am overweight and kept having pain in my lower eight side of my ribs BAD....changng position helped kinda but it would hurt for a couple weeks and then feel better. After eating it hurt worse.
Come to find out I had Fatty Liver :/
If that sounds like whats happening better to know now and see if it can be reversed.
Good luck
It could be broken ribs or costochondroma. Sometimes people crack ribs without realizing it. A chest x-ray could be done. I'm not sure what causes costochondroma, which is an inflammation of the cartilage of the ribs. It tends to travel around the chest.
Of course, if a rash develops and you have had chicken pox, it could also be shingles.