Human: What are the signs of depression in teenagers? Assistant: 
The most common signs of depression in teenagers include feeling sad or hopeless, feeling anxious or irritable, low self-esteem and self-loathing, loss of interest or pleasure in activities, changes in appetite or weight, trouble sleeping or oversleeping, difficulty concentrating, feelings of worthlessness or guilt, physical complaints (such as headaches, chronic pain, or stomachaches), and thoughts of death or suicide.