Worries?

I get a lot of negativity from others and myself every day. I'm worried and I think I have depression. My grades went down and wouldn't go up, I try my best at school but I just can't do anything right. I have jumbled feelings every day and they're all mixed up and messing me up. But I don't want to talk to anyone about it: it's considered bad if you get depression at my age where I come from.

But after reading some of the other posts in the forum, I started thinking like am I worrying about trivial, unimportant things? I seriously don't know what should I do now. All the help I sought here seems like an act of selfishness as I had kept other people who really need a listener to talk to from getting a listener.

To put it simple, I'm one messed up kid.