What Am I Riddles

Question: I hide when you wake but upset you as you sleep... What am I?

Question: Silent yet deafening. Invisible, but you know it's there. It can either make you laugh or it can make you cry. What is it?

Question: What's higher than mountains, Smaller than trees?

Question: I am duplicate of you, but only lighter. What am I?

Question: Wind and cord combine, buzzing in the box. In all this we find, though to some the use is lost. What am I?