Girls, My girlfriend's TOO playfully aggressive?

She's being aggressive in a playful way, but I don't know if it's normal. Usually, I'll make a joke and she'll punch my arm or push me. Sometimes, she'll do it for no reason to mess with me. A few times she has hit me in the crotch jokingly. But is this normal? Do you do this with your boyfriends like this? Should I say something?
Girls, My girlfriend's TOO playfully aggressive?
Post Opinion