What do you think about me throwing pillows and hitting things with them?
Why did you hit it hard?
I was mad at it for not supporting my head while sleeping in the night.
There are times when we get mad and need to vent.   You should be careful to avoid damaging anything and express than anger in healthy ways.
What is the point of being careful and trying to fix issues when they happen? People will get mad and throw shit around.
If you are feeling stressed and angry I doubt it was the pillow that really set you off. Have you considered talking to someone about what is going on in your life? You can't hide behind the pillow and a bad night's sleep if you are having violent outbursts.