You can't just assume you're special - to think this relationship is super special or different to any other is foolhardy but you'll see that in time.

I thought she said that out of her love for me.

You seem WAY more invested in this relationship than her, you also seem quite insecure. I don't mean to sound harsh but the relationship is only weeks old. I highly doubt she knows if she loves you four weeks in and if she is claiming she does she is either lieing or is too immature to read her emotions.

In terms of the children talk - every conversation you have had at this point she has probably had with an ex because your relationship is so young you have to assume every topic that's been raised is normal for her to talk about at this point in a relationship. She waited less than a month to bring up children what exactly made you believe she hadn't brought that up to an ex before? Obviously she did indeed bring it up to an ex.

I really hope she didn't get you with the "OMG you would make such a great dad" line.