I'm not compact, apparently

I had a fun encounter with the cashier at Bed, Bath & Beyond yesterday. Here's a rough outline of our conversation:
(without any prompting from me that I was pregnant...) Clerk: Congratulations. When are you due?
Me: Oh, thanks. In August.
Clerk (looking surprised): Oh! You've got a ways to go still.
Me: Yup, not there yet.
Clerk: Is this your first pregnancy?
Me: Yes.
Clerk (with raised eyebrows): Really? Are you having twins?
Me: No...
Clerk: Well, I guess I just carried very compactly in my first pregnancy.
Me: Oh.

So, I guess I am not carrying this baby very "compactly"... though the doctor just told me on Friday that I'm in the normal range for weight and measurements right now.
It wasn't until I got out to the car that I started to think of the comebacks I should have used during this pleasant conversation. I suppose she wasn't trying to be mean, but who in their right mind tells a pregnant woman (in so many words) that she looks fat?!

Not cool. But I don't care. I ran my five miles this morning. And I'm gonna eat some corned beef and cabbage tonight and follow it up with a big bowl of ice cream. So there!