I AM FREAKING OUT!?! EVERYONE HELP ME!?!?

I was home alone yesterday and as I went to bed I was really craving a gl of water. I went to the kitchen and one of the drawers were open. A knife was out and all sorts of utensils were tered on the counter. A window was wide open. I freaked out! I quickly closed it. I went to the phone to call the police, but the moment I put my hand on the phone it ringed, I answered and there was heavy aggressive breathing on the line. I closed went to a corned and curled up in a ball. I was so scared I started to bite my nails. I got another call I answer and a deep voice said "don't you know it's a bad habit to bite your nails".AAAAAAH. I am not at my house right now, I am staying over at a friends. But I am still SOO scared, I can't get over it, I keep thinking about it and i could have gotten killed