My partners name..

I'm 17 36+2 weeks and I've decided to respect what my partner (baby's dad) wishes and to give our little boy his second name when he is born and I don't know what the future holds and if we're going to stay together for a long time and get married even if we don't I would like to change second name to his just so I can have the same name as my child.. I wouldn't want to change it if we split up. Just wanting people's opinions on it? I have spoke to my family and his and they are all okay with it.