Robert Pattinson is ''worried'' about finishing 'The Twilight Saga' due to the ''fragile'' economy.The actor, who plays Edward Cullen in the vampire franchise, admits he got ''scared'' at having ''less control'' towards the end of filming the movie series compared to feeling ''free'' while shooting the first instalment. The 26-year-old hunk was joined by his co-star and real-life girlfriend Kristen Stewart, who plays Edward's wife Bella Swan, in one of their first joint interviews since she publically admitted in July she had cheated on him with married 'Snow White and the Huntsman' director Rupert Sanders. Speaking on 'Entertainment Tonight', he said: ''It's slightly worrying. It's a fragile economy at the moment. ''I felt a lot more free in the first ['Twilight' film], it felt quite dangerous. This one, you know your fate is still going to be at the front of it, but you have a lot less control than the beginning so it's kind of scary.'' Whereas Robert worries about how his life will be affected when 'Twilight' finishes, Kristen, 22, believes the pressure of starring in the successful franchise was ''worth it''. She added: ''It makes it incredibly worth it. As soon as you don't have that pressure, what are you doing it for?'' The brunette beauty also joked about the expectations of filming the vampire love scenes, joking: ''You're supposed to have this mind-blowing, inhuman experience. How do you do that?'' The pair and their co-stars Taylor Lautner, Ashley Greene and Kellan Lutz can be seen in the final instalment of the franchise 'The Twilight Saga: Breaking Dawn Part 2' next month.