CaLi does this aLLLLLLLL the time. I have got her stuffed(durable) dogs, and she wrestles and flips em over, tackles em, pins em down, drags em, pounces on em, hides from em, barks etc LMFAO!!!
I even found one that has a little matchbox size device inside and you can record a 'message' (it was a cheesie Valentine's gift from an Ex

) anyways, I recorded a long on-going Wuf wuf wuf..grrrr woof woof grrr 'message'.....this is genius. She bites the ear and stimulates the toy and plays forever.
This actions are totally normal. I think its a plus that you have a dog with personality and "pretending" skills. also, its self entertainment abilities.
Sometimes if I wrestle and roll around with CaLi and throw her toys for 10 mins or so...then put her in her pen...she goes after he doggies like..."ok now who's gonna get this first?" lmfao!! Like she's opening a can of whoop some butt...hahaha. Only start to worry if your dog nips or starts to be aggressive AT you...