Scotland
Littlejohn represented Scotland at Under–15 and Under–17 level. At the Under–19 age group, Littlejohn was part of the side which qualified for the 2008 UEFA Women's Under-19 Championship in France. She scored Scotland's only goal in a 3–1 defeat to England at the final tournament group stage. Littlejohn scored 12 goals in her 15 appearances for Scotland's Under–19s.
Scotland's senior national team coach Anna Signeul excluded Littlejohn due to personal differences: "Em, well, the senior manager wasn’t a fan of mine. I think she thought I had too much carry on, a little personality, and she wasn’t really into that."
Ireland
After three-year of not playing internationally, Littlejohn situation caught the eye of Arsenal teammates Emma Byrne, Yvonne Tracy and Niamh Fahey. They alerted the FAI to her eligibility through her maternal grandparents.
In February 2012 Littlejohn received her first call–up to the senior Republic of Ireland squad, for the 2012 Algarve Cup.[24] She made her debut with the Irish national team against Hungary at the final game of the Algarve Cup on 7 March 2012. Ireland won 2–1 to avoid a last place finish. Altogether Littlejohn has so far been capped 54 times by the Irish.
