Things will look better after proper sleep Annie. And I'm sure your son is going to bounce back super fast. Bouts of anxiety and depression don't always have to turn into big deals like a lot of us here suffer from. I've known plenty of people who have a crisis then come out the other side again pretty quickly.
It's good that he has you and the counsellor to talk to about anything on his mind. Have a good sleep and stay optimistic.