Her foot does not look good. She probably had bumblefoot or another infection before you stepped on her, so she couldn't move out of your way fast enough because of it. I would start soaking her foot in warm Epsom salt water at least twice a day for a few days. Depending on how it's looking, you...
Did you step on her hard? Quails are pretty fragile, so it's possible you broke some bones or did some internal damage. How does her poop look? Has she been eating and drinking okay?
The bottom of her foot looks very swollen and/or infected from the pictures. Possibly bumblefoot. Can you get...