If you have been suffering some of the following symptoms most of the days, all of the day for at least two weeks you may be suffering from depression: Persistent sad, or anxious. Feelings of hopelessness or pessimism. Feelings of irritability, frustration, or restlessness. Feelings of guilt, worthlessness or helplessness. Loss of pleasure in hobbies and activities. Decreased energy or fatigue. Difficulty concentrating or making decisions. Difficulty sleeping. Changes in appetite.