Can you get dh to slowly palpate all along your back and ribs in the painful area and see if he can locate if there is an exact sore spot? If not specific spot shows up then move outward.
If nothing shows up it the places he can feel, maybe it is a deeper thing.

Are you drinking plenty of fluids?

Ages ago I had a few bouts of infections in the tube that goes from the kidney to the bladder. Sneezing, coughing , laughing , deep breaths would cause a intense stabbing sharp pain in the side under my ribcage and slightly around the back.
It was a killer pain..
I had no bladder infection sx at all at the time.

just thought of this so maybe if dh can't locate anything on the surface , muscles ,or bones, maybe a reg MD visit to check for this..