Even when I'm not trying to drink a lot of milk I kill at least a half gallon a day of whole milk. SO that's about 1200cals in milk alone. I couldn't see anyone gaining much off 2.2k cals per day. My Advice to any teen is too eat whenever and whatever possible.
If you want something reach out and grab it.
"What lies behind us and what lies before us are tiny matters compared to what lies with in us." Ralph Waldo Emerson