There can be several causes of severe gum pain, including a decayed tooth, trapped food, or an abscess. If the pain isn’t constant, you might have an exposed area of decayed tooth that was irritated by a piece of food. If the pain continues, it could be from small pieces of food stuck between your gums and teeth. Try rinsing your mouth out with warm water to see if that helps. If the severe gum pain is constant, it’s possible you have abscess, which is an infection of the tooth and gum. See a dentist as soon as possible to get treatment for an abscess. Treatment might involve taking antibiotics and pain medication, and you might also need the infection drained with either gum surgery or a root canal.