i'm also 17 and.. okay, I'm guilty, i use looooots of make-up products everyday too.. but that's because I love playing with make-up and try all sorts of new techniques, but I think I could easily cast aside some of the items I use in my daily routine..
I do use foundation, sometimes concealer, loose powder everytime, bronzer, sometimes cream blush on the apples of my cheeks, sometimes both bronzer and cream blush, various shades of eyeshadow, eyeliner, mascara, illuminator, gloss.. and I see a lot of my friends who really don't wear that much makeup! But I think the secret is to choose colours that work for your complexion, textures that flatter your skin, use a really light quantity of make-up.. and make sure to blend everything together well!
I'm in the process of going as much as I can back to basics now.. :)