Nicola Roberts has revealed that recording her solo album made her ill.
The Girls Aloud singer told The Sun that she put herself under a lot of pressure while recording Cinderella's Eyes.
She said: "I came down with a cold and was like, 'I'm making myself ill'. I've never felt stress like that."
Nicola added that she had no qualms about arguing with her producer over the sound of the tracks.
She said: "If a track's slightly changed it doesn't give me the same feeling. So when the producer's like, 'It's not changed, I haven't done that,' I'm like, 'You have. I don't feel the same as when I first heard it. So we either argue all day or you just admit you've changed it and change it back'."
The singer also said she didn't know if Girls Aloud would make another album.