There is nothing you can do in such a situation other than to ensure there is no objects or walls it could whack. If so throw some padding around it.
My brother's little dog had a fit last year and the family assumed it had a brain tumour. Seems they were wrong as it is fit and well and no further witnessed episodes, so maybe caused by a passing problem.
Hope your little doggie is OK. At least if it's a brain tumour it will be painless and as the condition worsens gives you time to come to terms with the inevitable need to have the dog euthanized. Hopefully it's nothing much. Dogs can be prescribed anti-seizure medication if it persists.
