Is a pain because you will be unable to focus unless it's something you enjoy doing which makes you hyperfocus or hyperfixate. It can take you 5 hours to do a task that would normally take you 30 minutes because you keep doing something else by accident.

Third of all: Hyperactivity causes you to disturb classmates and the people around you. This is the same for stimming in ASD. That means you have the necessity to mask. Masking is very harmful in ASD. It takes a lot of EF and in the best case will cause dissociation, in the worst case it can drain