Weird "ghost" story?????

i was a little kid and sleeping at my grandfather's (who had just died, we were there for his funeral) house. i woke up randomly in the middle of the night, and remember watching the little nitelite plugged into the wall (yep, i used a nitelite :)) flicker out, and then this weird whirring noise started. It was quiet and doing slow circles around the room at first, but then it got louder and faster until it was almost deafening. after a minute or two it abruptly stopped, and i fell back to sleep. my brother sleeping one bed over did not wake up during the whole ordeal, and i know i did not make this up or dream it. i don't believe in ghosts per say, but remembering this experience is making me reconsider. what do you think happened?