I am by no means an expert, but I understand that dogs can have different types of seizures. Not all seizures are the grand mal type seizures that we commonly picture. Sometimes dogs will run, poop on themselves, "vocalize" (involuntarily -- so making sounds doesn't necessarily mean they are in pain) etc, during a seizure.
Here are a couple of online resources from veterinarians on seizures:
http://www.hurricaneanimalhospital.com/forms/info%20handouts/Seizures.pdfhttp://www.vetmed.wsu.edu/cliented/seizures.aspxIf it were me, I would write down as much as I could remember about the incident -- what day it was, what time of day, where it happened, what Star did, what he ate that day, literally everything I could think of. Hopefully it was nothing serious, but if it was a seizure and it does happen again, you might be able to discover a pattern. And videoing this sort of stuff -- if you can react quickly enough to get it on camera -- is always a good idea. It can't hurt, and it could help with diagnosis.