Bless you Emily, for trying to help this dog. I know she will appreciate the kindness and shelter you are giving her wile she is injured.
You don't know what injuries she could possibly have received from the accident.
There may be some internal injury you don't know about.
Of course it would be better if you could take her to a vet for X rays etc.
Is there an animal charity which would help her -for a donation only? And not a full vet's fee? Is there one in your nearby area? (I have no idea where you live...)
If not, is there anything you could sell in order to raise some money for the vet? A car? A computer? Jewelry?
This dear dog needs as much help as you can give her. You are very kind to take her in and try to help her.
There is a chance of couse that with rest, light food, and water and your love, she will recover. But that is a blind guess, and probably a dangerous one, as you have no idea of the extent of her injuries.
She Got run over, sorry for the auto correct.