I've nursed a couple back to health. They at times kind of setup triage in my garage and me and the wife make sure that they have water and food and a warm place to recover.
Before the mean old power line people came and cut down all my trees, we used to watch 3D squirrel races. They'd chase each other around and up and down the tree trunks at full speed.
BTW, Factoid - there's never been a reported case of rabies from a squirrel according to the CDC. Ticks me off when people talk about squirrels spreading diseases. This is not what they used to have on their website, but...
Small rodents and other wild animals
Small rodents like squirrels, hamsters, guinea pigs, gerbils, chipmunks, rats, and mice) and lagomorphs including rabbits and hares are almost never found to be infected with rabies and have not been known to transmit rabies to humans.
CDC - Other Wild Animals - Rabies
Hope the little fuzzie had a happy life after his fall.