Zoomies are very common and often occur out of the blue. Yes, it can be scary if you don't know what's going on. When My dogs start this I tell them to 'take it outside' and htey are then free to zoom around to until they collapse from exhaustion!
Yeah he definitely zooms around without cause and really funny to watch, then followed by a collapse
The first time we thought he was going crazy on us and If you try to stop it he will try to gnaw at your hand in anger ( like leave me alone i'm the exorcist )
I always called it the"puppy crazies"-- and thought it was normal for puppies. I have never had an adult do it--maybe we are not talking about the same thing -they just start running around like little maniacs for about 5-10 minutes and then they stop--- and usually go to sleep-used to happen here about 8:00 every night