Baby ear piercing

Hey so my Baby girl is two months old and I wanted to pierce her ears but I hadn’t done it because I’m me and my boyfriend wanted to go together and today she went to my moms house to spend the night since she is always asking me if I can let her stay with her for the night and I’m going through some things and I was like okay only for tonight (I already miss her so much) so I was checking up on her see how she’s doing my mom tells me she opened her ears and I’m upset so I tell her that she shouldn’t had done it and she gets upset and calls me selfish saying that I have no word and that I’m just waiting and it’s gonna hurt more as she grows… am I the one wrong here? I mean I told her no and she’s my baby… my mom already had that chance with her kids; I want to have those moments with mine too