So i am switching apps and for about 10 seconds there is a pure black screen. I notice that the center of the screen is not pure black. In the center of the black screen there is a large faint slightly white fog-like spot - about the size of an american quarter. When the app appears it has a black background and I can still see this spot is still there behind the text. Anyone else notice this? Is this normal - or do i have a screen problem developing?