Answer:
A reaction to being spooked that takes its name from waterfowl
We are all around, yet to us you are half blind. Sunlight makes us invisible, and difficult to find.
My first keeps time, my second spends time, my whole tells time.
A man went to the hardware store to buy items for his house. 1 would cost $.25. 12 would cost $.50. 122 would cost $.75. When he left the store he had spent $.75, what did he buy?
What goes in, but never through? I've got some and so do you. We might lend one, or even two, but only if our trust is true.
I never sleep yet sometimes I weep. I can get angry or just be happy. Wherever you go, I will follow. No matter what you do, I will be there. I cannot die. What am I?