Its very very unlikely to be pancreatic cancer. You would likely have a whole load of other symptoms including jaundice either on your skin or the whites of your eyes, feeling or being sick, weight loss, pale stools, pain etc.
An ultrasound scan is not the best way to look at the pancreas anyway as a great deal of it is hidden and cannot be seen by ultrasound.
You would be far better having a CT scan with contrast, but the first port of call is to have bloods done, if these were normal it is very encouraging.
I had a lot of your symptoms when I had gallstones. I have since had my gallbladder removed and still have some of the symptoms. Pain is not always in the traditional right sided under-the-ribs pain, my pain moved around and included should blade pain, belly button pain and left sided stitch type pain.
To be honest it could be anything from ulcers, GERD, anxiety, SIBO, pancreatitis, gallstones, gallbladder dysfunction, liver problems, and many other things. Only your doctor can advise and arrange the appropriate tests.