The 'One Day' actress insists she was always "professional" on set but didn't always take the advice she was given by directors.
She said: "I think I used to be a lot better at speaking than listening and missed a lot of wisdom that was coming my way as a result.
"I was so afraid that if I didn't say things loud, they wouldn't get heard at all.
"I wasn't a nightmare – I was always professional – but I think, maybe I was a little young and arrogant."
The 'Love and Other Drugs' star also admitted she is bemused as to why people associate her name with romantic comedies as she has "never" starred in one and just looks for "honest" movie choices.
She told Britain's Marie Claire magazine: "It's funny because I recently found out I'm mainly known for romantic comedies, but I've never actually made one.
"I've just been very honest about the films I want to do. That's as much of a strategy as I have."