I went to a boarding school in England for one year, when I was 16 years old. It was a really old building, imagine it like 300 year old castle, which it basically was. The windows were ancient and would let in everything smaller then your finger. Therefore, there were mosquitos AND spiders. Now I hate every insect in this world but this goes double for spiders. So one night I would lay in my bed, trying to sleep. As always I could hear the mousquitos buzzing and I knew that there would be spiders as well. So when I was in the sweet state between being awake and sleep, I felt something moving in my nose. In horror I totally froze for a second but realised I had to react before the thing, whatever it was, in my nose could get even higher up. I could actually feel the warmth of that damn thing in my nose. So I kept shut my other nostril and snorted as hard as I could, while I was running to the bathroom. Still holding my nose and snorting I turned on the light and looked at the mirror. After my eyes got used to the light I discovered that I was covered in blood. Turns out I had a nosebleed and I had mistaken the river of blood in my nose for an insect. I don't know if you ever had a nosebleed and sneezed, but this is pretty much how it looked like. But not only me, my sheets and the way from my bed to the bathroom had little sprinkles of blood everywhere. Needless to say that I had to come up with a story to tell the cleaners, laundry-ladies and my Head of Boarding, who had been alarmed.
TL;DR Thought I had something crawling in my nose, tried to get it out, was only a nosebleed, blood everywhere.
Edit: Formating