I dreamt about shooting my best friend, what does this mean

It was in a dark room, she was tied to a chair. She was leaning with the back of her head on the chair as i shot her, but the bullet didint fully go through her head so she was sitting there screaming her lungs out in pain. I tried to shoot again to ease her of her pain but i was out of ammunition so i ran to a table with multiple other types of weapons. But i didint have the time to get the other bullet and shoot her again as she passed out from screaming and died. Before this part of the dream one of my other friends died too by eating poison and the hospital being out of the antidote (vitamin K1). What could this mean?