macbook air cracked screen

I am so frustrated. I have been an Apple customer for ages. Ths is my 5th Apple laptop. I was reluctant to purchase the MacBook Air because it looked too flimsey. I and only I use this computer. I shut it down and when I went back to it, I noticed a crack in the lower left hand side. I did absolutely NOTHING to it nor do I use pens/pencils or any other objects when I use it. Apple refused to cover this. I have only had it for a few months. I am very disappointed in this computer and Apple. I feel this computer is defected. Anyone else have this problem?