You should read the first version first to learn about this. There is a lot I left out though. After I wrote it I started trying to recall more memories. And I remember more. I didn't have too many direct experiences, considering I tended to stay away from my room, but I remember how it felt, and what I felt. It didn't feel like it was mine, and at night I felt alone, but like people were there.
I remember walking down the dark hall at night, and looking into my room, which was lit by the moon, but released darkness into the hall, as if it was light. And it was the only room my new cat never took the time to explore, despite how curious he was about the apartment, and even though entities like this have seemed to avoid him. I also didn't describe the heartbeat incident well enough.
When I entered my room, I noticed that it was unusually gray inside, despite it being sunny outside. And I felt odd when I first entered, and almost immediately knew that something was wrong. I wanted to leave as soon as possible, so I decided to clean quickly. But then I heard it. It was as if it was straight out of Edgar Allan Poe's "A Tell-Tale Heart." When it beat, it was not only the sound, but its pulse seemed to flow through everything, releasing fear and panic in greater degrees each time. And later I still went in with no problems. I also had a few cases of sleep paralysis.
On a few nights I found myself awake, but still sleeping. What I felt and saw is hard to explain. I saw somthing, I don't know how to describe it, so I will just say living, but it seemed that I was only looking at a wall, and sometimes at the window. I knew it was looking at me, and I was looking at it, and I could see it so clearly, but not at all. I tried to close my eyes to go back to sleep, but it felt like they were already closed and I couldn't tighten them anymore, but I could still see it, as if my eyelids were clear. Sometimes it was hiding in the wall, sometimes staring through the window. And I couldn't really move anything else, and when it comes to nightmares, I am always able to move and wake myself up, it even became my normal response. But I couldn't move. But being who I am, I just stared back until I was finally able to sleep again, and continued to sleep in that room. But I've always felt like it feared me too.
I'm with RedWolf on this one, it was bad enough to read the first part of this story and I think part two does not do anything good or helpful to make us understand it better.
Your writing style reminds me of another teenage poster, "Love of my Life" whose stupid story got really bad ratings... She is not related to you, is she?