It appears that when I'm looking at an all white background on my screen, that somebody has turned up the brightness and when I look back to another, darker webpage, it's almost as if somebody is dimming the page. Is this because that page is darker and therefore appearing to dim things and vice versa or is this something to be worried about? I'm twenty years old and female who wears glasses. I do suffer from anxiety, so I don't know whether this could factor into it or not. Please help, I'm very concerned.