Oh Momo! You are such a sweetie!! What cute pictures!
I agree, NEVER hit your cat, it doesn't teach them anything, except probably to be more aggressive, if anything!
Kittens rough play alot, the have very sharp claws, and teeth. I am sure Momo does'nt even know she is hurting you, to her, she wants to play and wrestle, like they do with their brother's and sisters as kittens. It's natural kitty play. Part of that is kicking with their back feet, and biting, just like lion and tiger cubs do when you see them on T.V.
I'm sure she just loves to play with that stuffed animal, which is why she takes it with her, probably like a security blanket!
Good luck with her, and be gentle!