One thing that I know I did a lot is have an extremely exaggerated personality because of how bad your social anxiety is. You constantly think everyone is judging you, so you have this carefully calculated sort of facade. You seem funny and spontaneous and extroverted, easy to talk to and friendly, basically you become that quirky weird kid. You try so hard to be funny and likable, be just weird enough but in a sort of funny way, so that people will like you. Then you get home and are absolutely drained because you really have no social battery but force yourself to have one because that's what your carefully crafted personality calls for. You seem spontaneous and funny but really every move is carefully calculated.