I hope your cat is all ok now bless it. Unfortunately they do get under our feet sometimes - mine especially when im in the kitchen, bless her. They do seem quite robust though but do learn from their experience as they will keep out of your way for a few days, but only for a few.

Checking it over with your hands is always good and if they dont yelp then hopefully it is nothing too serious. Just keep an eye on it for a few days and see.