I have always good vision, but lately I noticed that my eyesight became blurry for about 15 sec whenever I whistled. Later I noticed that it also became blurry whenever I sang along to a song but for a longer time. After 5 minutes my vision comes back to normal. But now I have seen that my right eye vision becomes foggy at random times. It is not the same as when I sing or whistle because it is only on one eye.