I'm not sure what if any medical basis this has, but when Vin had this toenail ripped out, I didn't have anything on-hand like flour or Quik Stop, so we held his toe in a cold, damp facecloth for about ten minutes, and the bleeding stopped completely. If the flour doesn't work, you might want to try it. If nothing else, it can't hurt.
It looks a lot worse than it is. Vin didn't make a single sound with his toe (and he's a huge wuss who squeaks at every little thing,) so if he felt it at all, it couldn't have been much. His toenail grew back within a couple of weeks as well, but I know a girl whose ferret tore a toenail out and it never grew back, so I guess it depends on the injury and how it heals.