Bad dream

I just woke up now and I wanted to type out a little about this dream I just had. I actually forgot most of it, but I swear I heard of the story before. So there is this normal kid who grows up, and when he us 18 he goes I sand and kills people. No idea why, but he is just not right in the head. But the way I imagined it in my dream was seriously like a book I might have heard of before. I'm not sure if it is a book or not, and I have no reason why I had this dream.
The Plot of the story takes place in some prison like place. Though the first half was not actually in a prison but the second half was in like an outside and inside mental instutation.

I'm sorry I could not tell more but dreams are hard to describe. But I swear this was a book or movie or something.