I am not sure if that sort of trauma can break the hymen but I have heard that some girls can break their hymen whilst horse-riding. You may need to prepare for her to tell you she is bleeding (or may have to ask her).

I would ask her what type of pain it is and how does she rate the pain on a scale of 1 (not very painful) to 10 (excruciating) and ask her again in a few hours.

Hope she is ok - that would be very traumatic to have happen