Teen angst and moodiness is something you expect your child to go through somewhere around middle or high school. Although general sulkiness is par for the course during these hormonal years, sometimes these behaviors can signal a deeper problem. How can you tell if your teen is depressed or suicidal? Read on for signs and symptoms of teen depression, and find resources to help your child cope if you think she needs help. If you think your teen is suicidal or in immediate danger, call the National Suicide Prevention Hotline right away.