Hi NewMamma
Mine changes too. Like Lisa said it is normal. I have one page ranking at No 1
since I started and it really makes no sense at all. It is probably because my page has a title that no one else has. It was just a silly idea that I had.
I found "Pamela the Pilates Cow" on Flickr and it just made me smile at the time.
I decided to ask the owner if I could use the photo on my site as she obviously loves Pilates. My page ranks No1

I am sure it will dropped soon!