Hello ma'am!
This could be a case of secondary caries/decay in your tooth.
Could be due to :-
1. Inability of the dentist to remove caries in the first attempt
2. Deep decay in your tooth which could require a root canal , only to be confirmed on Xray
3. Poor oral hygiene
Next Steps
For immediate relief in sensitivity, you could use rapid relief anti sensitivity tooth paste.
Get the tooth checked asap to avoided further decay
Health Tips
For further information
visit www.zenithdental.in