After hitting a stray dog at 60kms an hour it.

If you pushed the brake pedal all the way to the floor when bleeding the line you most likely damaged the master cylinder. Crud and corrosion build up in the lower halves of the bores where the lip seals don't normally travel. When you push the pedal more than half way down it runs the seals over that crud and can rip them. Usually those brakes will still gravity-bleed but with a good master cylinder you may have to "irritate" the brake pedal a little to get the fluid flow started. If the seals are torn, irritating the pedal won't do anything and the fluid may never start to flow on its own.