Loud Bangs

To start off, I should explain the situation. Over this past summer, I barely spent any time home, and I spent a lot of time at my friend Elijah's. His house has a weird vibe to it and he's told me about some weird things he has seen/felt. Well, there was a span of the summer where I spent 4 straight days over at his house. And the first two nights were weird. On the first night, around 2 a.m., we were awake playing PS2. He was playing a game, while I was on the phone. The room door was shut, but we plainly heard a loud bang come from the basement. We first passed it off as something fell over, but ten minutes later, we heard another, louder bang. We decided not to check, and passed it off. We stayed up, got no sleep, and went down to the basement before his parents woke up, around 8 that morning. Nothing was out of place, so nothing could have fallen over. We didn't know how to explain it, so we thought "why bother". He booted up the computer, while I went to a fridge in the back of his basement to get a drink. In the minute I was there, I had the feeling I was being watched. I went back, and Elijah was still in the chair by the computer. We went out with a bunch of friends to kill the day after that and came back around 10. We went into the kitchen around 12 to get some food. While looking through the fridge, I saw something move quickly behind us out of the corner of my eye. Elijah saw it to, cause he whipped his head around to check. With that, we said "nuts" to the food and went into the room for the night.