Thanks for asking the query,
Oain in the filled tooth can be because of two reasons, there could be dental caries
left beneath the restored tooth which when reaches the pulp tissue causes inflammation of pulp known as pulpitis
Or there could be presence of high points if you feel pain at the time of chewing or other tooth movements.
I would suggest you to consult the concerned Dentist
and get an x-ray done and accordingly replace the filling with RCT or get it trimmed as required.
Take tab combliflam 500mg for pain relief.