On the day that this encounter happened, I was home with only my grandfather, just to clarify.
I woke up and began to stretch. Because it was a weekend, I was in no hurry to wake up. However, after I finished stretching, I heard a male voice say "Hey". The voice sounded like a young adult's voice, around 16 or 17. I froze, because the voice sounded like it came from right next to me. I contemplated briefly where the sound could have come from. The voice had no accent, so it couldn't be any of my neighbors, who all either don't speak English, or have an accent. I had no brothers. My uncle, dad, and grandfather didn't sound like that, and are too old anyway.
I walked out of the room. I was really scared, but I was determined to pretend ghosts didn't exist (my mom said I was starting to sound insane after I told her a few of my experiences). Then, as I walked, I heard footsteps right behind me. It sounded like the person had sandals on or something and was dragging his feet. I had been planning on eating breakfast, but I ran back to my room and fell asleep. Yeah, that's my attempt to pretend nothing happened.
I woke up again later, and again heard "Hey". I walked out, but those same footsteps followed. Rather than go back to sleep and have it happen again, I turned on the TV to try to make myself feel like I'm not alone on the first floor of my home. It didn't happen again, but I still remember.