Thank you for the query.
Your mothers symptoms seems to be not related to pancreas
disease. More probable is that her symptoms are caused by intestines obstruction (due to narrow connection of the intestines caused by recent surgery or by adhesions), cancer metastases (spot of her pancreas does not have to be metastatic).
can also appear with acute gastroenterocolitis and does not have to be a sign of new cancer source.
I suggest you to have colonoscopy
performed, stool tests, CEA, CA19-9 levels (if elevated, consider PET scan and pancreas biopsy).
Hope this will help.