"You know it's usually the guy who leaves, right?" She manages to laugh and not curse, though her impulse is to curse.
"...You coulda said all of that before we got started." She would have been able to consider it without all the "Sam's a gentleman and probably has wanted this for a while" and "The sex is great but he's a Winchester" thoughts in the way.
"So you want me to stay for breakfast, and you want this to happen again." She's just making sure they're on the same page.