Pain in rib cage

Hi, so this may or not be an RA question. (I do have mild RA.). We took a car trip this week - two days of four hours each in the car. After the first day, I noticed achy pain in my back around the rib cage. We’ve been home for two days and it’s still bothering me. Just aching, all around the back of my rib cage and some around the front as well that is starting to feel a little like heartburn. Is it just from sitting in the car? Not tender to the touch, not worse with deep breaths…

??