My Dog Keeps Sitting On The Floor Rapidly Sticking Her Tongue Out And Turning As If To Itch Something .She Can't Reach, She Has Not Got Fleas And Has Been Fully Wormed?

My dog has been doing the same thing, in fact he just did it again this evening. He licks at nothing very fast and turns around as if something is bothering his tail. His tongue just keeps going in and out of his mouth fast and it goes on for quite awhile. It has happened about 3 times total. I wonder if it is some sort of mild seizure.

My four month old chihuahua has been doing the EXACT SAME THING!  She just stopped and curled up and went to sleep. I'm tempted to take er to the vet in the morning because I'm worried something is wrong.