What can I do to soothe this toothache?

See a dentist. Toothaches are caused by many things. A dentist can help you find the cause of yours and treat it.
Toothache. See your dentist asap to determine the cause and make a diagnosis. In the interim, if you have no contraindications, over the counter Ibuprofen is more effective for dental discomfort that tylenol (acetaminophen).
Call your dentist. In the meantime take any otc medication that you usually take for a headache. It will help in the short run, but the longer you wait the worse it can get.