Actually I need to correct my prior post. Fox did say the photo was reportedly taken by her, they did not say it was taken in the mirror. Sorry.
This was taken with a flash, but not self-shot. Don’t believe me? Take a camera, hold it out at arm’s length, let it meter and focus, and snap the shutter. With a flash at 2.5 - 3.0 feet’s distance, your face would be horrendously over-exposed. Washed out completely. In a mirror, the flash glare would completely obscure the image. Try it.