That right there is part of it. He does look like he regrets the manner in which he let it slip. Padmé does understand the heat of the moment and how at times things may be said or done in a way that someone might not otherwise attend to it.

"Probably." Less blurting out unexpectedly and more sitting one down to talk about it. Of course her husband could have mentioned something... But Anakin has been off. She adds, supplying, "Leia."