Castiel could never presume to know what exactly Meg was feeling. He could attempt to possibly understand what he inferred her to be feeling, but it all stopped short when it came to anything that required her to actually say the words. To tell him what she in fact, felt for him. Thankfully, he didn't take at complete face value what she felt for him, because he would have assumed she didn't care about him as deeply as she truly did, simply because she'd left him that next morning.
He did look at her in confusion because she stopped short and stopped speaking. He wasn't sure what she was going to say, although his heart seized a bit with the hope that she would have said what he'd wanted her to say well over a week ago. He knew not to expect that, of course, so he buried that want deep into his heart, to keep from idly hoping for it. He could live with the satisfaction that she did in fact care about him and did so, against all the odds of what she was used to.
"You're going to accept my help now?" He asked her, as he tentatively reached out to her again, to give her that support she needed to get inside of the building safely. "I still have food, if you would like to eat." It wasn't much, of course, but he would offer her whatever he could to help. He wasn't even sure if food would help a demon in this case or not. His guesses only came from observing the Winchesters for all of this time.