We're back from the vet. He said she doesn't appear to have suffered any effects from it and he couldn't find anything that could have caused it. I know she couldn't have gotten into anything toxic, she's never unsupervised. The vet said it could just be a one time thing and it may never happen again... or she could have epilepsy. He doesn't want to start her on any medications for anything right now.
Basically, he said just keep a close eye on her (which we do anyway). Write down last nights seizure and everything I can remember about it... time of day, events leading up to it, length of the seizure, how long it took her to come out of it, etc. He said if she has anymore to write down the info on those as well and give him that info at her next checkup and we'll decide from there what should be done. He said I shouldn't worry about rushing her in unless the seizure lasts more than 2 minutes and/or she has a tough time coming out of it.
So we're hoping it was just some kind of freak event and that it will never happen again.