Good Riddles

Question: I'm small but big, i hide behind you but come out when you fall... What am I?

Question: I'm just a lot of nothing but I'm every were... what am I?

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

Question: I run, I save people, and I was hit by lightning, And my public name starts with an "F"

Question: A man lived on the 12th floor of a building it was a nice building anyway when he goes to work he gets in the elevator and goes to the bottom floor. When he comes back he goes to the 7th floor and walks the rest. But when there is someone else in the elevator he goes to the 12th and when it is raining why.