hello and welcome HCM forum Mark,
I would like to inform you that the fractured teeth need a
root canal treatment at the earliest before the infection spreads. One tooth might have been fractured to a greater extent than the other one due to which the pain persists in one tooth only.
X-rays will reveal which one of the two needs a root canal treatment or may be both the teeth need a root canal treatment.
It is completely okay if the tooth is not sensitive and the filling has dislodged.
You don't have to get the filling redone until pain is present.
I will recommend you to see your
dentist soon.
The infection from the fractured tooth infects the nerves beneath it , it further spreads to the soft tissues which can cause a swelling if the treatment is delayed.
You can perform warm saline rinses(3-4 times/day), helps in relieving pain.
use an antibacterial mouth wash(twice/day), prevents infection.
Also, if the swelling appears you can take a painkiller, but this will not take care of the infection , therefore kindly visit your dentist.
i hope i answered your query,
i wish you good health
take care.