M.
Hi H..
My neighbor's son actually had something similar happen to him recently. Their ped. dentist told them they wouldn't be able to tell if the tooth had been damaged for 6-8 months. Basically, there is nothing you can do at this point. Just watch to see if it turns grey. If that happens, you should go and the dentist may want to remove the tooth. I would wait it out though after what I've heard the dentist tell my neighbor. At this point, there isn't much to do but wait. Good luck!
M.