I would try to talk to him more. I feel for you. But, I do not think he can have changed all that much in a week. The mentality he has must have already been there, I mean, he's a 14 year old boy...those hormones and those urges were there before last week, kwim? It's just that now he has this girl, who seems to be opening him up to the possibility of sex etc, making it real for him. I would honestly do as Trill and Jenifer have suggested, just make sure you really let him know the reality of it all. 14 is very young to be having sex for the first time, and from his mentality (you helping look after a baby) he has shown he just isn't ready. Are you close with his bestie? Maybe you could ask her to have a chat to him, to help him realise there is plenty of time for all of that. My brother was the same, my mum and I worried about him getting a girl pregnant for years but thankfully it never happened. He sounds like a really good kid, just becoming a terrible teen lol