It’s possible what you might consider a “nudge” with your boot, someone else might see as a “kick”.
Whatever the case, if I were your size, I might react the same way you would. As a woman who is smaller, I can see myself kicking or beating the cat away. As I said, I saw what cats can do. I don’t think this cat simply hissed and took a swipe at the man and his dog and then ran off. I’m assuming it scratched them up.
Of course, a cat hasn’t done that to me personally, so this is all talk. If I’m ever attacked by a cat, I’ll let you know what I actually end up doing (probably something like running away screaming). ;-)
video of cat attacking a Rottweiler