She left school at the age of 16 to pursue a career in acting, and enrolled on a three-year performing arts course followed by a degree in drama at Hull University.
[6] Her first television role came when she was cast as Rae Earl, a young woman who is released from a psychiatric facility after four months, in the E4 teen comedy-drama series My Mad Fat Diary (2013–2015).
[7] The show was a success and earned Rooney a BAFTA nomination at the British Academy Scotland Awards.
[8][9] The Guardian's Sam Wollaston called Rooney's performance "natural, effortless and utterly believable".
[13] In July 2016, she appeared in the ITV drama series Brief Encounters, set in 1982 and revolving around four women who become involved in Ann Summers party planning.