The singer, who may become a judge on The X Factor USA, reportedly became upset after reading American websites which labelled her as a 'no mark Brit'.
According to sources, the 27-year-old has also recently begun a new workout regime with celeb fitness guru Tracy Anderson.
An insider told Now: "Cheryl's finding it really tough to work out to Tracy's standards. She's also facing leaving everything she knows behind, including ex-hubby Ashley.
"She's going from a big fish in a small pond to a tadpole in the ocean."
It has also been claimed that Cole will not change her Newcastle accent for the American version of the show.