It is ok for you to have the bright spots in vision when you blink. Because when you blink, the eyeballs are in the moving state and the eye pressure is increased. The sudden blurry state is normal. After you calm down, such symptom will disappear. You could have a try.
Well, according to your description, you may have something wrong with your body health. I am sorry to hear that. Generally speaking, a lot of diseases could lead to that feeling, however, you should know whether your eyes have problems or not. Maybe it is just because of cold or just overwork. If you are still not sure of the cause, you should visit a doctor or do an eye test to see what is wrong.