has come because the cavity which was present has gone Deep and the infection
is now present in the bone surrounding the infected tooth.
You must see a dentist
as soon as possible so that proper measures can be done to control the infection with the help of medicines and root canal treatment
Ore extraction of the problematic tooth or teeth. Whether the tooth can be saved or not will be decided by the dentist depending on the structural damage to the damaged tooth. Do not self medicate and fix an appointment as soon as possible so that the treatment can be started.