The shooting happened around 10:35 p.m. near Carver and Loretto.
The victim was working at his father's store when he shot in the back and hand in the rear alley, officials say.
Police are reviewing surveillance video for information.
They say the rear door of the store had been kicked in.
The victim is hospitalized at Einstein Hospital in critical condition.
So far, there are no suspects or word on a motive.