Being homesick isn't about being away from home. It's being at home yet still feeling so empty and confused. Because what is home? Home is warmth and love.
You could be at home, yet still feel like everything is crashing down. You could be away from home, and feel like you're having the time of your life. You could be lying on your couch, idly watching everything and everyone as they pass by. Mindlessly active, totally passive.
Or maybe you're just homesick.