Im sorry to hear about your symptoms. Now the pain which you are describing can certainly be due to the gallbladder, if the gallbladder is inflammed it can cause a severe pain which radiates to the shoulder joint as well as the back. This can also cause vomiting, nausea etc in this case. This would be diagnosed best on the basis of an abdominal USG and also a HIDA scan if there is an element of gallbladder dysfunction.
Now while the CT scan is normal that should rule out pancreatitis as a cause for the symptoms, however it does not rule out an ulcer in the stomach which can cause this sort of pain. This would cause pain, burning, nausea, vomiting etc. The diagnosis would have to be made with the help of an endoscopy to look at the inside of the stomach. It is possible that there are multiple ulcers which can be causing the pain here. in some cases there can be a bacterial infection of teh stomach which is known as H.Pyroli which would need to be treated with the help of antibiotics.
I think the next best step here is to get an endoscopy done if it has not been already done, one more possibility is that you could have a gastrin secreting benign tumor on the pancreas which can cause ulcers in the stomach. this wouild be diagnosed with the help of a simple serum gastrin level.
I would suggest that an abdominal ultrasound be done to look at the gallbladder more closely followed by an endoscopy.
Do you have any more questions?
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