I have never really encountered a ghost, or I am not aware of it. But I have experienced quite a few strange things that are very hard to explain. This is one of them.
It happened about a week ago. I was having an unpleasant night, I had trouble falling asleep and my dreams were mostly nightmares. I woke up in the middle of the night. Even that was unusual, because I hardly ever wake up sooner than I should. But the strangest thing was the noise that woke me up. It was high-pitched and incredibly loud.
I sleep in a room with my guinea pig and I am quite used to the sounds it makes, so when I tried to find out what that noise was, I assumed it was the guinea pig. I had a hard time believing that, though.
The noise could be described as screaming of some agonized creature. It was unnatural and so loud that I heard it as clearly as before even when I hid my head under the blanket. I gave up the theory about my guinea pig making the sound, because it was just impossible.
The screaming lasted for several minutes. I expected and hoped that my parents would come and see what the noise was, since its source seemed to be in my room. I was sure they had to hear it too, because something as loud had to wake everybody. I waited, but nobody came to me. I stayed under my blanket and pillow, terrified, until the noise stopped.
When I woke up in the morning, I clearly remembered everything and there was no doubt that I had not been dreaming. I asked my parents about the noise and why they weren't terrified. They told me they hadn't heard anything and that it was probably just a dream. But I know it wasn't, it felt so real and terrifying. I only wish I knew what it was.