For your overthinking/SA/facial tension I suggest meditation. It makes you calmer. There's a million different ways, find one that works for you.
You have already practically won this battle by becoming self-aware and asking for advice. 99% of people don't get that far with their problems. Good Luck!
You have already practically won this battle by becoming self-aware and asking for advice. 99% of people don't get that far with their problems. Good Luck!