HELLO AND WELCOME,
as per your quiery,its not clear that whatkind of dental work have you got done,.
if you got your decayed tooth filled without removing the infected dentin
or pulp,it can cause such pain.visit your dentist
and get an x-ray of the filled tooth.this will help to rule out any periapical lesion if present.
depending on the spread of infection of pulp,pulp capping/pulpotomy/root canal treatment
has to be done.
also check whether your wisdom tooth has got infected.if so get it extracted.
avoid chewing food at the restored area.
usually given medicines are-tab.divon-100mg,twice daily for 3 days and tab.spamox-500mg-thrice daily for 3 days.
maintain good oral hygiene
.visit your dentist in every 6 months.