What causes a bad pain in my right shoulder blade and back pain/ seems to be the right side of my rib cage

An Ortho evaluation: When patients have persistent pain a good physical and exam can usually help figure out the causes which in this situation can include rotator cuff issues, neck pain, a pinched nerve or muscle spasm. An orthopedist or physical medicine and rehab can evaluate if a MRI is necessary and when to start therapy or other treatment. There are other non ortho causes of pain to consider like costochondritis.

Gall bladder pain?: It is possible you are getting referred pain from your gall bladder. Talk to your doctor about getting an ultra sound of your gall bladder.