Dry socket means an instant trip to the dentist, it will last until it's treated. Dry socket occurs when the blood clot falls out after an extraction, and the nerves are left open to the rest of your mouth, it's not a common thing. I had a tooth out last year because an impacted wisdom tooth destroyed it, and ended up with dry socket for about 3 days. The pain spread from the socket, right up the side of my face, I could barely move my jaw, and I couldn't sleep. I went back to the dentist as soon as I could, and the pain disappeared about an hour after he treated it.
If it's actually dry socket and not just normal post-dentist pain, go back tomorrow!