Severe upper adominal pain radiates through back lasts 4 to 5 hours, painkillers do not stop pain, sometimes vomiting. ultrasound/bloods show nothing.?

See a GI Doctor: Pain in the location & severity you are describing could be coming from the stomach, pancreas, or gallbladder (gb). An ultrasound is a great test for the gb, but not foolproof. Lab tests should be helpful for pancreas problems, but a ct may be best. Stomach problems are best assessed by endoscopy, performed by a GI dr. I recommend that you see a GI dr. To help get to the bottom of this asap.

Biliary dyskinesia: Could be a functional problem with the gallbladder. Ask your doctor about a nuclear medicine test called a cck hida scan. Should also pay attention to whether it not cck administration reproduces pain.