A toothache is not normal. It's a sign that something is wrong. You can address the pain of a toothache with an anti-inflammatory drug like aspirin or ibuprofen, but you should call your dentist immediately to set up an appointment. One word regarding aspirin: never apply aspirin directly to a sore gum. The acid in aspirin can burn and severely irritate gum tissue.
In some cases a toothache could be caused by nothing more serious than a particle of food stuck between teeth. Try flossing and rinsing your mouth with warm salt water. If that doesn't succeed in dislodging the particle, don't try to force the particle out yourself. Call your dentist.
When a tooth starts to ache – and that throbbing pain can get pretty intense – it's more likely that decay and infection has reached the tooth's pulp, the sensitive, soft tissue inside the tooth. So the tooth is going to need the attention of a dentist. The best way to avoid a toothache, of course, is to brush, floss and visit your dentist regularly.