What are considered the common warning signs of clinical depression?

Signs: Clinical depression can present as a constellation of symptoms lasting for at least 2 weeks. Mood can be sad, angry or anxious. There may be too much sleep or too little sleep. Appetite may plummet or markedly increase. Feelings of helplessness or hopelessness may abide. Loss of joy is a hallmark symptom. Social withdrawal & not engaging in normal activities is common. Concentration & memory may.

Worsening function: Depression can present in many ways, but worsening function, irritability, insomnia, negativism, and loss of zest are frequent presenting signs. Also, the omega sign (googl this) where the brow is furrowed between the eye brows is a common sign of depression along with darkening circles under the eyes and lack of fluctuating intonation in the voice, slouched posture. Etc.