I've seen coworkers that I'd describe as neuro-typical work in a similar way sometimes. But the tendency to alternate between periods of difficulty focusing and periods of hyperfocus is a recognized trait of ADHD. If you're interested in learning more I'd recommend Hallowell's book, the one I read was "Delivered from Distraction" but he might have a newer one. Just read the first couple chapters and if it resonates a lot then it might be worth getting tested.