Creepy night..

I have this really creepy and awry encounter last night!
I was in my study room using my desktop, unlike other days where I used my laptop in the living room..
So, it was around 1am in the morning, everone in my household was sleeping, and I heard some little kids playing 'OH YA PEH YA SOMP'.
At first, I wasn't suprised to hear them, but then I was chatting with my friends on MSN and I told them about this. And, their comments was 'CONFIRM GHOST'. Which convinced me and started believing.. As I was staying in the 11 storey, its quite impossible for me to be able to hear noises from downstairs. In addition, it was 1am. Which parents would be in the right mind to bring their children out at this timing?!
I was so afraid but still I looked down the windows to see if I could spot any little childrens, but no one was found! I gasped..
And I continued hearing them OH YA PEH YA SOMP, 3 times, exactly. I creeped and went back to room, hid under my blanket and hugging Cherry very tightly!

And by the way, this happened not only once! This is the second time already! The first time was something red passing by me when I was doing homework in my study room.. Now, I heard some little kids playing OH YA PEH YA SOMP while I was using computer in the study room..