[ Mental Health ] Open Question : Is this depression or just plain selfishness?

For the last three months or so since a classmate's death, I've been feeling low (obviously), like I fidget a lot, I feel as if I HAVE to go everywhere twirling my pen around my fingers all the time. I pace up and down a lot, feel physically exhausted in spite of about 10 hrs sleep/day, withdrawn from family, being friends is more of a burden now, have thought about death/suicide (not actually DOING it, but just ABOUT it, how it feels etc.), guilty most of the time, worrying about what I am doing is right or wrong morally, feel upset about the fact that I am adopted too. feel as if everything is so superficial, i wonder if it is really happening or not, everything seems pointless. I'm a (nearly) 17 year old female.

Source: http://answers.yahoo.com/question/index?qid=20110314005857AAJ2fmy

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