Why do i get a toothache every night?

Abscess ?: When you lie down the blood pressure will increase in your head and neck area. An abscess can start to throb as the pressure around the lesion increases. Better have it checked out by a dentist.

See a dentist ASAP: If you have a toothache, you may have a cavity or advanced gum disease. A tooth pain won't go away without treatment and the infection may spread to your jaw, cheeks, sinus and to other areas of your head and neck. You can use NSAID OTC or Tylenol (acetaminophen) for pain control. See your dentist ASAP.

See dentist asap: could be a cavity, infection,tooth fracture or other cause.