Not a matchup he wanted at all! Understatement.
I think Manning craves another ring because (I think) Manning wants to be universally acclaimed the GOAT. I think he is shocked, chagrined and more than a little pissed off that fate allowed a lowly 6th rounder to insert himself into what Manning deemed "his era".
Tom Brady has certainly stolen much of the thunder that, otherwise, would probably belong to Peyton. And I think there is a burning resentment of sorts, not necessarily directed towards Brady, but rather, towards fate itself. Manning's body language says it all, and betrays his innermost feelings.
No, not the matchup he wanted. I think he'd rather have his fingernails ripped off one by one or his balls crushed in a vise, than face Brady again, given the choice!
And that pressure, that burning need to "show the world" is probably (hopefully) what does him in again, as it has on so many other occasions.