That Jo manages to knock the girl down into the ground doesn't stop the concluding fact that following it Jo does a face plant into the floor once the girl goes straight through it.

The sickening smack and the swearing that followed would be just that happening.

Jo might be rethinking that part about not damaging the girl's body (a little) as she shoved her own back up into a crouch, doing her best to shut out the pain entirely.

She felt for her gun, as she glanced over at Dean, "You still alive over there?"