A Close Encounter

I went to the restroom about 10-15 minutes ago. While I was in the restroom, I heard what sounded like someone coming up the stairs and walking towards the restroom. I figured it was my youngest daughter waiting in the hall to go to the restroom, but when I looked there was no one there. I washed my hands and went to go downstairs and from our bedroom, someone came down the attic steps and walked over to the door. our bedroom door is locked( hook & eye) with a slight opening to the door. I seen something through the crack of the door and got the most uncomfortable feeling from it, so I went downstairs fast, but calm.