Someone watching me

ast weekend, when I was in the ferry boat, I tried to take some pictures behind the window (glasses of the window), there was a cold wind outside. Anyway, I was trying to take seagulls' picture. When I came home and when I uploaded to my pc, I noticed that someone was watching me :) This was an interesting, an eye! It should have been because of the reflection on the window but who can explain this eye... It is like an eye!