This is the house that the old man and the narrator share
Throughout the next 8 days, the narrator watched the old man and made up a plan to kill the old man(His father)
The Narrator kills the old man
The old man and the Narrator (his son) share a house together and live together.
That was me who screamed last night. My father is at the auction
In the house that the old man and the narrator share, the narrator watched the old man for the next 8 days, he couldn't stand his vulture eye so his plan was to kill him so he didn't have to look at the eye any longer.
Fine! I killed my father!!
After those 8 days, it was the night that the narrators plan was going to happen. The Narrator waited for the old man to go to sleep and once he was asleep, he flipped his bed and suffocated the old man and later started hearing his heartbeat in his head because the narrator knew what he had done wrong therefore he was going insane!
Not only did the narrator kill the old man, when the old man screamed during the night, the next morning the police wanted to know what the sound was and the narrator lied about what the sound was and said that it was him who had screamed during the night and then come to find out, the old man was supposed to be at an auction that morning and he wasn't there so the police were also very concerned about that as well.
After the police finished investigating the house, the police were talking to the narrator and the narrator could feel and hear the old mans beating heart in his head so he finally confessed that he had killed the old man all along.