“don’t make such a strong decision now because u might change your mind- people always change as they grow up”

It’s like he’s talking about himself and trying to convince nobody but himself. Does he really wants a child or does he only wants it because of his partner? Because that might be the reason why he started to suddenly interrogate you like this. If he chooses to be a father now he won’t be able to change that later ever in his life (as he said) he might regret it and he won’t ble able to do nothing about it because now he is a father forever. But if you choose not to have a child now and you really changed your mind you can just have it in the future so his logic only applies to his case basically.