dutchdog, are you sure that something didn't happen to be updating at the same time? Coincidental, sure, but possible. Eight photos chewing through hundreds of megabytes is certainly odd, unless they were pics from the new Cannon Super Giganto Jumbo 500 megapixel Huge Immense By God Just Really Big digital camera. LOL.
Also, do you have Facebook set to not play vids automatically? Something could have been playing during this time. Just throwing out ideas.