ok, a similar thing happened to me, 2 dogs ( not mine) got into my pen and killed 2 chocks, the other one was very subdued, panting heavily and looked a bit mashed up, no blood as such but had been had.
my partner at the time told me to kill it, it wont survive blah bla.
me being a soft touch decided to bed her down in the nesting compartment of her cage, she was kept in the dark and quiet, and as she would not Move to eat or drink i was taking her water on the hour and food once a day, no joke this went on for 3 weeks with little improvement, i even began to doubt it myself, HOWEVER.......... 3 days later i saw her head peering round the opening and witnessed her come out to eat. she gradually got stronger and made a full recovery! im so glad i did not listen to my partner, it depends how badly hurt yours is mine was clearly just stressed and badly bruised.
hope she is ok good luck they can be hard yer than u think but the main thing is not to let her suffer.