I am so sorry Hassan!!!!! I wasn't really myself.
Why Amir?!!!!!! Why?!!!!!!!!!!!!
Amir just finished his story and wants to show it to his dad and hero, Baba. When he shows it to his dad, Baba only replied with 'K' since he has no interested in hi son's story. This makes Amir sad and it hits him in the feels
Hassan and Amir were walking on the streets of Kabul when they enter an alley. As they were passing through it, a soldier appeared and started to insult Hassan for being a Hazara. This irritates Amir as he does not want to see his friend being treated with such disrespect.
As Amir sees Hassan being angry, he realized that he had done something terrible to his friend. He hated the way he acted upon his friend because he punched him on purpose.