I have a little peke who is being treated for seizure activity.
First -- seizures can .. not make that *are* made worse by panic and being nervous. Yes, it's difficult to see, but please -- try to remain calm, it is absolutely *essential*. You can actually make them seize *again and again* just simply by being so over-wrought yourself that it causes the animal more trauma (same thing with a human, actually).
A blood test likely won't tell you much of anything at all -- it's a good idea, it will give a general good idea of health, but it's not going to pop up a banner and say "Yep, this dog is ...."
The medicine for seizures has **many** side effects -- long term it is very very difficult to take, and regulate. Phenobarbitol is one and potassium bromide is another -- you do*not* want to put the dog on either of these drugs unless it is absolutely without choice. Here the vets up at the U of Florida actually recommend treatment with acupuncture and herbals if at all possible, and not to even consider drugs until there are at least 2 seizures or more a month.
We control all of Kee's seizure activity with herbals and acupuncture. It took a while to find exactly the right combination but it's well worth it. She doesn't have the "grand mal" seizures, but rather she can be in a seizure mode almost for hours doing an almost obsessive type of seizure activity (you can't hardly get her attention at all), but the herbals are astonishing.
Because you and your spouse were home, compare notes and try hard to remember the dog's behavior immediately prior to the seizure and even a couple of hours before.
Was the dog extra clingy? Or acting at all unusual? Maybe avoiding you, or alternatively not wanting to be alone? Lying in a strange place? Such behavior is often repetitive - and it can help you identify PRE-seizure activity so you can sometimes stop the seizure before it starts.
Keeping some valerian root on hand can be superb. It's a nervine herb that is a relaxant, and can help you settle the dog down if you suspect another seizure might be about to happen. English valerian is about the best you can get in the world. A dog that size can take a full adult dose every six hours without any harm at all. The ground herb mixed in with something yummy (even a wee bit of Bisto and water or peanut butter or anything yummy). (The Americans on here are saying "What's Bisto?" but my husband is British and you wouldn't BELIEVE what I pay to get Bisto here in the States!!)
You may also get a clue by seeing if the dog could have been chewing on something outside? Pine can be a culprit -- was the dog in any sort of pine pitch or pine cones? Do you use pine cleaner in the house? Any possibility he got into anything toxic? Any plants he might have nibbled on?
good luck -- if you want to email me, I have a friend who rescues seizure dogs and she's marvelous at describing how to calm them down. I'd be happy to give you her email address if you'd like.
Just sitting down, petting the dog calmly and just talking calmly. Talk about the weather or anything silly -- read a book even .. just keep your voice and tone calm and soothing.
But don't 'worry' over him. Don't be too "oh dear oh dear" -- to make him really think something horrid will happen. Just be calming.