Your dog may be having a partial or aura seizure. This type of seizure does not render the dog unresponsive as full blown epileptic seizure would, rather you will see behaviors that are abnormal . These behaviors /seizures can last from minutes to days in duration. Some dogs will pace, circle, hide, snap at imaginary flies, lick, become clingy to the owner, act frightened, and the list goes on. Here is more on this.
Some breeds are more prone to epilepsy then others but it can happen in any breed of dog. You didn't mention what breed this is so I am going to direct you to a site on dog breeds. Click on your breed and a page will open. Scroll to the bottom and it will tell you the prone illnesses. If thiis a mixed breed then click on the breeds that make up the mix. http://www.petplace.com/dogs/akc-breeds-alphabetical/page1.aspx