Kristen Stewart seemed more uncomfortable than ever at Sunday's MTV Movie Awards, dropping her Best Female Performance award and admitting to fans that she is "awkward."

But her Twilight and New Moon costar, Peter Facinelli, tells Usmagazine.com, "That's just Kristen. I think she has that shaky knee syndrome and that's part of her charm."

See what Kristen Stewart and all the stars wore to the 2009 MTV Movie Awards

"To sweep the awards like that? If that doesn't build someone's confidence, I don't know what can," he told Us Tuesday at the NYC premiere of Showtime's Nurse Jackie.

See red carpet pictures of Robert Pattinson at the Twilight premiere

As for Stewart's sudden rise to fame, "I think being mind-blown about it isn't the same as being uncomfortable with it. I think she's got a real charm and grace about her, and I think she really is settling into it. We had a great time filming New Moon and we're all really excited for the next one - Kristen included."

Watch the New Moon trailer!

He said the vampire sequel (out Nov. 20) is now being edited.

See an early photo of Kristen Stewart - and more!

"Hopefully they'll pick the good parts and make a good movie, Facinelli told Us. "I'm excited to actually see it.

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