The 23-year-old singer, who landed the role of Mia Grey in the erotic drama, said she was so nervous that she could not remember her words, reported Contactmusic.
"I had to have someone in my ear on set telling me what to say before I said it because I was honestly like so nervous I forgot everything that I had learnt," she said.
However, the blonde beauty credits her co-star Dakota Johnson - who plays the leading lady Anastasia Steele - for helping her get over her first-time acting fears.