1. Sometimes there are cavities between the teeth that not visible on the surface.
2. If it's sensitivity to hot and cold foods and beverages, this could be 'dentinal hypersensitivity' which can be relieved by using a desensitizing toothpaste such as sensodyne.
3. If it doesn't respond to the toothpaste, you'll need to take antibiotic and pain medication to get temporary relief till the time dental clinics reopen.
Next Steps
1. Try changing you tooth paste to a desensitizing one such as Sensodyne for 2-3 days.
2. If that doesn't relieve the pain, have an online consultation with a dentist of your choice using 'Practo Consult' feature to get a medicine prescription.
3. If pain is still not relieved after taking medicines, you'll need to visit the dental OPD of a hospital that is functioning with adequate precautionary measures against corona virus.
Health Tips
Avoid hot fomentations (garm sikai). It may cause a swelling.