scratch & dent on rMBP "13

after i buy my macbook pro on july, i and school is start again, and after i go school for 2 month i started to realised that my macbook has a small dent on its lid and after i inspect it further actually i have some dent in back north left side (from trackpad view) and i also have a jaggered edge in the body, not the lid, and i also have a small dented edge on the lid,and few scratch on the bottom side, this make me surprised, i still under warranty should i sent to the apple store or i just buy skin/case??, and can someone give me advice how to care & use macbook properly, because im complete noob here