Could Aiden have just hurt herself jumping down off a higher surface?
If she continues to act better, some anti-inflams could be all she needs.

I have a cat limping around here...she jumps on the kitchen counter and it's a hard drop down to the floor.
She's got a bruised leg but I can't keep her off higher places, she doesn't get that's why her leg hurts.

Nice fall day for us...
Dinner is CP chix thighs, baked taters and broccoli.