The right word for what Dave is feeling right now is overwhelmed. As in he's completely and utterly overwhelmed.

Seeing his comics turned into actual movies. Apparently movies that were incredibly influential and amazing (really, they're pretty much shit) was pretty mind boggling.

He had no idea how to react to this. Mostly, he didn't know how to react to it without looking like a completely uncool spaz. Or absconding. Shit. If he just sits here like a fucking rock, maybe that would work. That's a fucking dumb idea and he should feel ashamed for considering it. He should be trying to be all smug because hey, he's some super cool movie producer. Naw.