There very normal. We call them 'zoomies' over here. It's like when their energy level goes over the top and they just can't stop themselves! I've love to see a vid if you have any, 'Lo hasn't had the zooms in a few months now. Don't try to stop Jersey, just stand back and smile, these are mostly a puppy thing so enjoy then while they last.
That's funny, we call them "zoomers"!
As a puppy Benny used to go into these fits like clockwork at 7:00 every night. Our neighbor even commented "oh it must be 7:00, Benny's zooming again." He'd start running around the yard, tail down, like a little brown bullet. Then he'd start attacking the first person he came in contact with. He would grab the ankle of our pants (or sock if we were wearing shorts) and not let go. If we managed to get him off, he'd start zooming again. It was the funniest thing you'd ever want to see.
Nowadays Benny rarely zooms. Once in a while we'll manage to get him so excited he'll take a couple of laps, but that's it. The days of these 5-10 minute fits are over.
The only time he'll really zoom is when it's snowy out and we dig out paths for him in the backyard. He'll run around the paths as fast as he can. That has stopped too actually. Benny discovered he likes jumping into the snow! So here I am, getting a full workout making these paths for Ben, and he doesn't even use them. He likes the deep snow...