Have you had an experience that you suspect might be a ghost, but not sure?

I'm not sure whether I should believe in ghosts and spirits or not. I lived in an old house for about 4 years, and I heard and saw some things that really seemed paranormal, but I just don't want to believe it. I actually saw a full length cloaked figure standing in the hallway that appeared solid, then when I turned and looked straight at it, there was light shining through it from the window over the stairs. Then it just GLIDED swiftly down the hallway and into a bedroom and disappeared. I stared into the room, and couldn't see anything in there, but I wasn't brave enough to actually go into the room. I still can't accept that I really saw a ghost.