I remember going to the barn one day and being told that the night before the horses had gotten out and run down the road (pavement); my horse's front knee was swollen, and he wasn't bearing any weight on it. I panicked, thinking the worst possible scenerios...tendon injuries, broken bones, etc. I called our vet while I was hosing it down, and gave him the run down, and he suggested just doing what I was doing, along with giving him shots of banamine throughout the next 24-48 hours and see what happens. He also suggested putting a mild liniment and lightly wrapping it, to further reduce the inflammation and discomfort, especially so that if we eventually needed to get an x-ray, it wouldn't be clouded by the fluid and swollen tissue. I left him in is normal paddock, rather than cramping him up in a stall, as he was quiet out there anyway, but of course, that wouldn't be an option for everyone. Anyway, within 12 hours, there was a very noticeable difference; he was standing mobile on four legs again, the swelling was greatly reduced, and he was moving much more freely. The next day, you couldn't tell that anything had been wrong, although I still gave him 2 weeks rest, just to be sure. Soooooooo...hopefully, your girl just had too good of a time, and is just sore. Do you have pain medications? Have you hosed her? Do you have light bandages you could wrap her with, to give her a bit of support?
"The ideal horseman has the courage of a lion, the patience of a saint, and the hands of a woman..."