"Seeing stars" is a common visual complaint, but it is usually a normal and harmless occurrence. Most of the time when you “see stars,” it is a result of changes in blood flow to your brain that can happen if you get up too fast or feel dizzy from riding a roller coaster. Seeing stars or flashing lights can, however, be a sign of a retinal tear or detachment. When the retinal layers separate from the eye, the retina becomes stimulated and gives off a flash of light. Usually this flash of light is accompanied by “floaters” such as specks, lines or spots in your vision. If you have this symptom and it last longer than an hour, see an eye doctor immediately.