You feel bad because you've done something that is totally different from what you would normally do. That's okay. How were you to know he was going to prepare dinner? You did what you needed to do in order to keep the peace and harmony w/your kids before going to your grandparents.

I wouldn't worry about it, i.e., as he stated, it can be reheated today.

Sit quietly, the answers will reveal themselves when you least expect them to.
The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.