What a sad dream that i had !?

Last night i had a dream that I was at the supermarket. At the supermarket their was a boy who had a gun. He was about 7 or 8 years old, he wanted to shoot me. All of the sadden i took the gun away from him and give it to the owner of the store. At this supermarket my partner works there. So the owner of the supermarket shoot my partner by mistake. But he only shot him on the back of his leg. Why did i dream this ? What does it means?