The most possible cause of pain is infection due to cracked tooth. You can take over the counter medications like amoxycillin. Also take Ibuprofen, it will reduce swelling and pain. Start doing warm saline gargles at least 4 times daily.

Here are some of the useful tips to deal with the pain due to cracked tooth:

1. Avoid too hot or too cold beverages.
2. Avoid acidic or too sugary food stuff.
3. Floss between the cracked tooth. It helps to relieve the food particles and thus prevents spreading of infection.
4. Place cotton dipped in eugenol oil (can be obtained from medical shops) over the area. Make sure not to swallow it.
5. Some pharmacies even keep a temporary sealing material. So, it is advised to fill the crack with those temporary sealing materials till the time you can't see a dentist.

For more info on cracked tooth visit the link....http://www.identalhub.com/articlecategory-cracked-tooth-56.aspx