Checklist:
1)Is there any swelling?
2)Sensitive to cold Or Hot?
3)What increases the pain, like any food, tea, cold water, or sleeping/ lying down on bed etc?
4) How is pain relieved?
5) Any crackling sound on opening and closing of mouth?
Next Steps
X-ray of upper and lower molars, to check any caries, or not.
or OPG
Health Tips
Visit a Dental Surgeon, or respond here with proper clues given above, So You may be helped further.