There is always something that could potentially upset us and that causes a lot of people not to be able to function properly.

Aggression is not a bad thing, providing you can put it into a hobby. Some people burn up a lot of that energy into exercise. A punching bag is the most obvious source to channel your aggression for reasons that should be obvious.

And writers can also turn that aggression into a positive. You can gain plenty of inspiration from being upset and that can be channeled into your writing quite nicely.

So don't be worried if you get angry, rather channel it into something positive and make the most out of a bad situation.