Suffocated While Sleeping?

I've been living in this house for almost two years now, and there has definitely been some paranormal happenings going on. Although I'm not going to get into them, I was just giving some background information.

I was sleeping in the same bedroom as my 9 year old, younger brother. We were sharing the bunk bed. I was on the bottom bunk, he was on the top. It was midnight when I went to sleep, and around 3:00 in the morning was when I was woken up abruptly.

I was lying on my side, facing the open space of the room. I woke up to feeling cold hands or fists pressing against my face, practically suffocating me. It almost felt like they were punching me.

My face felt numb and I couldn't breath, so I flipped onto my back and threw the blanket over my head. I was just about to take blanket off, I was grasping the edges of my sheets. Then I felt something weighing down on my chest, like something was sitting on it. Again, I felt like I was being suffocated.

I was gasping for air, and after about two minutes, I yanked the blanket off and looked around the room. There was nothing there, and the weight on my chest had lifted.

There was just enough light in the room to see what was there and what wasn't, and believe me, I saw absolutely nothing. I checked if my brother was still on the top bunk, and there he was sleeping soundly.

In the morning I asked my little brother if he had woken up at all the previous night, and if he saw anything and/or felt anything, he told me he did not.

Now I've been searching all over the internet trying to figure out what happened that night, or if it is common. Most of the sites talk about sleep paralysis, but that is when you hallucinate and can't move. So obviously It wasn't that.

I'm not sure of what happened that night, but I would really like to know.