Hi there ~
I understand your concerns. The
MMR vaccine is probably not the reason for pain behind ears and back, as well as swelling under jaws and ears. I also think that you should not be afraid of any of these issues with side effects from the vaccine. What would bother me though is an
ear infection that might need to be looked into since you also have a
sore throat. I hope your geriatrician is giving you antibiotics for the same.
I hope this helped and I wish you the very best. Take care!