Pain is a tool that we have to protect us from harm. The pain in your tooth is telling  you that something is wrong and it needs to be fixed.
See your dentist as soon as possible about your toothache if:
a. You have a toothache that lasts longer than 1 or 2 days
b. Your toothache is severe
c. You have a fever, earache, or pain upon opening your mouth wide
d. You have a swollen face
Pain from nerve damage may result from teeth grinding, severe tooth decay or trauma to the teeth through injury. Intense, throbbing pain, sometimes accompanied by a swollen face, is often a sign of an infection or abscess.
Throbbing tooth pain is often associated with inflammation in or around the tooth caused by infection in the center (the pulp) of the tooth, infection of the gums, sinus infection, cracked or chipped teeth, broken crowns or fillings. Whatever sort of pain you experience, sharp or throbbing, your brain is telling you that there is a problem that needs to be fixed.