Thread: Last night I dreamed that my little brother cut his hand, and I don't understand why

This is one of the most disturbing and unpleasant nightmares I have had in a while, and it made me feel pretty depressed when I woke up.
I dreamed that me and my little brother were fighting over something, and a while later he went back to his room and cut the back of his left hand, and it started bleeding.
I obviously freaked out and stopped him, and he furiously yelled "let me wait for the blood to run out!" and passed out.
I tried to talk to him while carrying him downstairs, and my mother (she is a nurse in waking life, by the way) told me that it looked alright and that he would survive - and I could see that his wound had almost healed all of a sudden.
Then we put him in an armchair, and he tried to say something, and then I screamed "shut the hell up and wait until mum has treated your wounds, you acted like an idiot!".
And the dream ended there.

What the hell was this all about?
We are like best friends in waking life, and often spend time together, and I seriously cannot quite remember the last time we had an actual fight.
I actually started crying just by writing this post, and I cannot make any sense out of this at all.
Why would I dream something like this?