What should I do if I can't stop remembering this?
I'm not sure what memory you are referencing. Can you explain please?
I don't know it's like this feeling that I simply hate the world
It's okay to be unhappy. But this could be trauma, you should seek professional help.
No, I don't care about it anyways.
It's good to reflect on your feelings to understand yourself better. Doing this will help you to be more aware of why you think and feel the way that you do.