The update on this little boy owl is that he probably got into some poison by eating a poisoned mouse. I took him to the Rogers Wildlife Rehabilitation Center.
He had a little blood in his eye as well so he probably became disoriented and flew into something as a result of the poisoning. Check out this link for tips on what to do if you find an injured or sick bird:
By the way, it is not only wildlife that can suffer from eating a poisoned mouse. Pet owners should always avoid using any kind of harmful poisons or garden chemicals.