TW, what a discouraging start. It does sound like the meds might have to be reviewed now that he has day to day stressors and triggers acting on him again. The hitting himself is a real giveaway.
Don't give up hope because there it may take a while to find balance. I'm glad he's finally getting help with his mental health, as well as continuing out-patient and family involvement.
Does he have any exercises he can do to relieve anxiety - meditation?
All the best with this continuing process.