According to the National Institute of Mental Health, there are four common types of depression, also called depressive disorders. However, within these types there are variations in the number of symptoms, their severity, and persistence. Different feelings and perceptions include emotional flatness or emptiness, hopelessness, loss of self-esteem, and suicidal thoughts or actions. Any one symptom probably doesn't mean depression. There is a risk for developing depression when there is a family history, and this risk may be somewhat higher for those with bipolar depression.
Additional factors including stressful environment and low self-esteem can lead to depression.
I also feel down after having fights with my parents or friends. Less successful students may feel depressed because they feel they have not achieved academically because of an active social life. Severely depressed teenagers may progress to suicidal behavior. According to St. Clare's Hospital Department of Consultation and Education, suicidal behavior includes verbal suicide threats, previous suicide attempts, and final arrangements like making a will or giving away prized possessions. However, depression can be treated.