hi there the problem you describing seems to point toward abdominal trauma which is common after fall. since your grandmother was taken to ER and Xrays seems to be OK so it is unlikely that there can be perforation type of problem. however if abdominal size is increasing gradually then other causes of swelling of adbomen should be ruled out like hematoma (associated with fall of BP), Intra-abdominal abscess(associated with fever). in my opinion in such case patient should be again sent to ER for further investigation like CT or ultrasonography to find out real cause of swelling. kindly be careful about sudden worsening of abdominal pain in the days following injury with suspect of having a ruptured solid organ hematoma or a delayed hollow viscus perforation, particularly if have tachycardia and/or hypotension. so kindly get the patient checkup in ER throughly TC