Baby’s last name...

I am currently not with my father of my unborn child, and even when with him I originally planned on giving our baby a hyphenated last name, because even if we were to stay together, I would also hyphenate mine once married. Well now that we’re separated, and I have read a bunch of stories about parents who regret their last name choice, it made me think, should I just give the baby my last name? My mother loves my baby’s father, and she is very persistent when it comes to telling me to give the baby his last name, but I can’t help but think, why? I’m the one carrying this baby, I’m the one going through it all, I’m the one that will be the primary caregiver, so why should it get his last name? Am I being selfish?