The 22-year-old actress admitted she is embarrassed by her attempts at a "sexy face” during the romantic scenes with real life boyfriend Robert Pattinson.
She said, “It's nice to see your own reflection while your making 'shmexy' faces. It's absolutely absurd, I want to shoot myself.”
Kristen also revealed she found it easy to quit smoking because she was never addicted to nicotine.
She explained to chat show host Conan O’Brien, "I was a bit of a faker, a circumstantial smoker. I just feel like I wasn't addicted to nicotine. I just wanted something in my mouth."
Meanwhile, Kristen said starring in the Twilight Saga film franchise was a “once in a lifetime” experience but she was not impressed with the contacts she had to wear when her character became a vampire in the final movie.
She said, "Those red contacts are awful - like, tunnel vision, wallpaper eyes. I think I've been sitting around for years watching everyone else do it. I've played [Bella] every step of the way as a human, so that final one made so much sense to me, I was raring to go."