Очень нужно проверить сочинение на ошибки!
So, it happened last week and I wish, I’d forgotten this. It was a deep night. Glad I bought 2 packs of coffee beforehand, because that day I have drunk 3 or 4 cups. 7 chapters of my new book were ready, 5 of them I have written during the day and 2 - at night. I had to write 3 more chapters, even though my eyes were closing. Otherwise, I'd have lost my job. My new book was about a haunted house: I was really good at horror books. I sought some new ideas in my head, something that could terrify the reader. But I knew that it wasn’t really easy, to amaze people in our days. Then I suddenly felt that I should get some fresh air. I left the house, shut the door and sat on the stairs. Then I took out a cigarette and lit it. The moths flew into the light of the lantern. I began to reflect and found out that I was completely out of thoughts. Suddenly I heard some noise on my left. I turned around and saw a little abandoned house. That was strange for me because I was sure that I have never seen this house before. I understood that there was something wrong and tried to listen, what kind of noise was there. And then I heard that somebody had shot. I sprang up and ran towards the house. I had no phone in my pocket and I couldn’t call the police. I rang the doorbell but of course there was no answer. The door was locked and I hit the window with my hand, but it hadn’t broken. So I chose one rock that was the biggest and threw it through the window. Then I was able to open the door from the inside, but I hurt my hand on the glass and it bled a little bit. I came inside the house. It stank a lot and it smelt like something was spoilt there. Some paintings hang on the walls and some strange liquid was spilt on the floor. Someone sang on the second floor. I went upstairs and entered a small room. A girl stood in a long white dress in the middle of the room, sang a strange song and wept. Her face was pale. Suddenly a terror gripped me and I couldn’t move. I made an effort and turned my eyes to the bed that was in the corner. One little girl lay there. Her eyes were closed and she slept. I hoped, that she slept. Finally, I pulled myself together and fled out of the room. Downstairs I stopped and caught my breath. I saw a door that led to the backyard. At the next moment I looked down and saw that I hold a gun. I really had no idea what was going on. I quit the house and entered the backyard. I saw a lot of strange children, they were also very pale and worn very old, dirty and ragged clothes. They didn’t notice me and that meant, that they didn’t see me at all. One girl read the Bible, another girl spoke to the little boy, who had just built a big pyramid of cubes. He didn’t understand her at all. I saw also a pond and a two girls. They swung on a swing near the pond. All of them looked really happy and I put down the gun, not to scare them. At that moment, all these kids stared at me. They became angry and appalling. I was completely terrified and didn’t know what to do. I tried to scream or run, but I couldn’t, like someone has bound me. I might have been nailed to the spot with the shock and with horror. But then everything disappeared and I felt something. Someone shook me. At that moment I woke up. My mom has brought me something to eat. I fell asleep, while I was writing the book! So, I ate these toasts with great pleasure. Then I asked for the delay and managed to finish the book. I sold it well. But then I decided to leave the job and take a break from all these horrors. Otherwise, I would completely lose my mind after one more dream, like I have already had.

Перед словом because запятую ставить не надо?

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I was really good at horror books.

Ведь ты по идее всё равно умеешь хорошо писать хорор книги, нет? То что ты перестал их писать, не факт что ты уже не хорош в этом... Ну в любом случае я только хочу уточнить, Вы то лучше разбираетесь. Это пока всё.