Sally Hawkins always worries she has "f***ed up" on a movie set.

The 'Made in Dagenham' star admits she is unsure if she is a good actress as she is always critiquing herself and thinks she can always improve her characters.

Asked what it is that makes her stand out as an actress, she said: "I don't know if I know yet. You think, 'That was ok in that bit' or 'I really f***ed up there'. You just hope that you'll be better next time or that you'll get a next time.

"There are always things you can work on. Some things are more successful that others but really, all you know is what you like and what makes it sort of work for you."

The 34-year-old star - who won a Golden Globe for her performance in 2008's 'Happy-Go-Lucky' - also admits she doesn't want to "indulge" herself by thinking she is the leading lday, despite being the main focus of the 'Made in Dagenham' promotional posters.

She told The Scotsman newspaper: "I think if you indulge in that then it's a very slippery road and you'll probably trip yourself up. It's part of the job.

"There will come a time when it's not happening and it'll be lovely to look back and have that experience.

"But it is tricky and you have to remember that it's going to be ok. And for a while you just have to walk past those posters. But they're nice for my mum to have!"