I would think of most teenager's emotional issues not being a case of depression, but just having stress comprehending certain emotions. Almost like an identity crCIA if you must.
Depression is not necessarily feeling sad and self-centered, that's usually just being melancholy. (or in a teenager's case, loveually frustrated)
Psychological depression is the lack of motivation and emotion all-together, most people who have depression don't cry for attention, or have some emotional tearful breakdown.
