Pcos? teenage female, skinny, small breasted, extended pubic hair growth, mood swings, depression, periodic emotionless. what's causing it?

Hormone imbalance: If you have PCOS, you are not ovulating and may have excess male hormone levels. You need to talk to your MD about treatment. OCPs will regulate your cycle and supress the elevated male hormone levels.

See psychiatrist: You may be having eating disorder -afraid to gain weight called anorexia nervosa ,along with having emotional problem it can be at school ,friends or at home or work.since you have problem see your doctor who can do investigation for any medical problem, but must see a psychiatrist as well f or your mood swings -to have psychotherapy medication .