The Girls Aloud singer - who will release her debut solo album '3 Words' later this month - is terrified of stepping into the spotlight without her bandmates.
The 26-year-old star told Sugar magazine: "The thing is, for the past seven years the other girls have been my safety blanket. If I forget my words on stage or something, there's always four other girls that can pick it up.
"Now I'm completely on my own. I wake up in the middle of the night sick with pure fear going, 'What am I doing?' "
Even though she is frightened, Cheryl is also excited to be challenging herself by pursuing a venture on her own.
She explained: "It's good to feel frightened. Being out of your comfort zone isn't always a bad thing."
