Dog constantly spins in circles?

I'm dog-sitting my friends dashund, and ive never seen a dog do this before. She is constantly spinning in circles, she doesn't know how to walk in a staight line. she follows me while spinning, and when i sit down she walks in circles around me. I've seen in cartoons and videos dogs spinning a couple times when they get exited, but with this dog, its a constant thing! Is this anxiety? is she too hyper? is this even normal?????