My necklace randomly disappeared then reappeared out of no where?

I always hang my necklaces in the same spot. I went to go wear that necklace for the day, and it was missing. I checked the house high and low and couldnt find it. Then I decided to look back where I first checked and it was there. I asked my mom and dad and my brother, and none of them said they even saw the necklace. I'm a little creeped out, but I have been living in my house for about 16 years, and its over 100 years old. Could there be a ghost in the house?