How do you kno if you suffer from depression?

Seek an evaluation: Depression as an illness (usually meaning major depressive d/o) has multiple symptoms inclusing depressed mood, decreased enjoyment, sleep problems, appetite and weight loss, thoughts of death or suicide, focus and motivation problems leading to impaired functioning. If you think you may have this illness, get help.

Depression symptoms: As dr. Nash mentioned, you may be suffering from depression if you have a certain combination of depressive symptoms. You can do some some self rating for depression to "check' if you might have it. Zung depression scale is one of the questionnaires you can use. Healthnet.Umassmed.Edu/mhealth/zungselfrateddepressionscale.Pdf if you believe you have depression, see your pcp or a psychiatrist.