We need to know if there is any caries in the tooth where it is paining.
I am assuming that there is a caries in a particular tooth and this have reached the pulp and hence the pain.
The pulp has the nerve vessels which innervate the tooth.
Next Steps
First there needs to b an x Ray done of the paining tooth.
If the caries is involving the pulp then RCT can b done otherwise the next line of treatment depends on the x Ray.
Health Tips
Avoid chewing food from that particular tooth.
Avoid too hot and too cold fluids.
Warm saline mouth rinse will help reduce .
Taking too much painkiller is also not good.
Visit a nearby dentist asap.