Tricky one Rhianon. D'you think he's genuinely worried about the money or that's just an excuse because he doesn't want a second child?

If this is the first time you've discussed it, you could have just caught him offguard and he may have just seen a huge bill come in so that money was at the forefront of his mind.

I think you definitely need to talk more when you're both relaxed and have a bit of time up your sleeve. Maybe go out for dinner if possible.

If he really doesn't want another child, I think you need to listen to his reasons - neither of you is right or wrong but you need to resolve it one way or the other.