Have vast amount of experience in tooth 'smashing' situations.
DS1 while 3, was mucking about with DH and managed to bash his front teeth on a tiled floor, snapping them both off halfway, leaving stumps.
He then went on to hit the stumps and detach his top lip from his gum at pre-school after slipping on a tree stump, then a few months later, tripped out my Mum's front door landing flat on his face on the concrete step (he was wrapped in a blanket pretending to be a sausage so couldn't put his hands out to break his fall) which finally loosened one of the stumps and caused the root to poke out the top of his gum iyswim?
So..... I know what sort of day you have had and totally feel for you as it DOES look horrific.
The first time anything happened, we saw an emergency dentist who basically told us they are milk teeth and don't matter - they have no nerves so shouldn't cause any discomfort and the jarring would probably not damage the tooth behind.
He has managed to bash them twice more since then, as above, so am a bit worried now tbh that he may have damaged the other tooth behind. The second time I took him to A&E when I picked him up from pre-school I asked the dentist we were referred to if they would take them out as he seems accident prone in this dept and without stumps to knock the other with, surely he would do less damage if he did it again, but they were not too interested as it would mean having to have him sedated.
Thing is, they have since gone rotten as they are snapped so open across the bottom, look awful and actually smell.
Bit of an essay, but want you to know I have been in similar situations and all the blood is awful and the swelling, but, all the blood supply to the area means it heals incredibly quickly too.
Hope your DD is better soon, poor mite. x