Hi XXXXXXXX~
What you're describing does absolutely sound like a seizure. The 'paddling' that you're seeing is a classic symptom of seizures.
If this were my dog, I'd get him in to the vet for a complete work-up. There are so many possible causes for seizures that it's hard to know what is causing them, however they are somthing that is considered an emergency (especially new onset seizures)and often times the seizures can be controlled with medication.
I hope this helps.
Certified Veterinary Technician
Associates Degree in Veterinary Technology. State and Nationally certified.