Depression shows up different symptoms that person can know if they are in depression or not, includes:
Lack of interest in daily exercise activities
Feeling nervous and depression
Lack of hope sense
Bouts of crying for no apparent reason
Sleep disturbances
Difficulties in focus and concentration
Difficulties in making decisions
Increase or decrease weight unintentionally
Nervous
Anxiety and weariness
Touchiness
Feeling tired or weakness
Lack of value sense
Loss of interest in sex
Suicidal thoughts or suicide attempts
Physical problems without explanation, such as back pain or head.
Depression could be levels symptoms among men and women, but for teens this disease will be dangerous especially if they have family problems, you can imaging how dangerous is.