Limping appears worse?

Hi all so one of my new girls started limping about five days after we got her. She is two months old and from a farm. She has a little friend and they run, jump at eachother so we thought she landed funny. My boyfriend checked her leg and cant see any obvious swelling or fractures. So we put her on crate rest. We are now on the third day and to me she seems a lot worse. She cant balance and is falling over. She is still eating.