She will attend the UK premiere tonight with her on-off-on beau Pattison.
The actress, who will attend the film's UK premiere tonight with co-stars Robert and Taylor Lautner, added: "I started when I was 10 years old so I definitely wouldn't trade anything."
The 22-year-old - who reprises her role as Bella in the final instalment of the Twilight Saga, Breaking Dawn Part 2 - has been the focus of tabloid attention, due to her on-off relationship with co-star Robert Pattinson, and is constantly chased by paparazzi and the films' fans (aka Twi-hards).
"There have been some heavy moments obviously but I would trade nothing," she said.
"It's such a strange job; you need to be a little crazy, you need to be a little obsessive. Also being so young it's really rare... how often do people find what really genuinely challenges them in life at this age? I get so much more time to do what I love than most people do."
Kristen, who was 17 when she was cast in the first Twilight film in 2007, admitted they never knew that the series would become such a huge phenomenon.
"We didn't even know a sequel was possible. It genuinely wasn't the goal," she recalled.
"It definitely had a following but I think we all imagined it was fairly cult-ish. And then when it suddenly took like wildfire, it actually made sense. It's not like it was expected but it was like if anything was going to do it then it made sense it was this."
The Twilight Saga: Breaking Dawn Part 2 is released on November 16.