Im depressed & idk if i can do this.

I can't concentrate in school at all anymore. Everything feels wrong, i get up and go to school everyday. I pretend to be happy...but as soon as i get home i go to my room, lock the door & cry.

Im gonna talk to a psychologist for the first time on Friday & im kinda worried because there r so many reasons why im depressed....so many that i don't even know all of them...and idk what im supposed to tell him or her when she asks me whats wrong...