The British actor, 22, said he is finding it difficult to deal with the expectations from fans of the Stephenie Meyer franchise.
Pattinson, who played Cedric Diggory in the Harry Potter movies, claimed that the fandom surrounding Twilight is similar to the wizard films.
"It's similar, but I feel a lot more pressure now," he told Digital Spy. "I remember doing the Harry Potter one and no-one cared about me, they all just wanted to see Daniel [Radcliffe].
"It was much easier. This time it's very scary and I'm like 'Argh!'"
Speaking at the movie's London premiere, he added. "It's quite shocking. I was worried that I would come back here and there would be just ten people and no-one would have heard about me!"
Twilight opens on December 19.