You should see your dentist
. Tooth pain comes from exposure of a nerve root inside the tooth to the outside, usually due to break down of the protective hard cap of tooth over the top of the nerve. This occurs usually due to cavities (dental caries), but also can occur due to trauma to the tooth, such as a chipped or cracked tooth.
The appropriate thing to do is to have an exam of the tooth by your dentist, because this pain should not be allowed to go on for long without being looked at. If there is an exposed nerve root, the cavity or defect in the tooth could serve as a site for a more serious tooth infection. This could lead to loss of the tooth or the need for a more expensive or extensive dental procedure or, in rare cases, an generalized infection in the body.
While waiting for your dental appointment, you can talk an antiinflammatory medication like ibuprofen or naprosyn for the pain. You should also avoid very hot or cold liquids, as these tend to irritate the exposed nerve roots. Other popular remedies like peppermint oil are helpful sometimes for certain individuals with tooth pain.