Nikolija debuted with her single 'Ćao zdravo' (Bye, Bye) in March 2013, without intentions of pursuing a music career in Serbia. Same year she was featured on the lead single 'Milion dolara' (Million Dollars) for Ana Nikolić's fourth album. The following year, she was a contestant on Serbian version of Dancing with the Stars. Then released hit singles 'Alkohola litar' (Liter of Alcohol), a collaboration with Elitni Odredi, and 'Kako posle mene' (How After Me) in August and October, respectively. However, in August 2015, she had the biggest success yet with her solo single 'Opasna igra' (Dangerous Game). Her debut album, titled №1, which included songs that had been released since the beginning of her career as well as three new tracks, was released on 20 October 2016 under City Records. In March 2017, she released an electropop single 'Promeni mi planove' (Change My Plans). She had a hit with 'Loš momak' (Bad Boy), but saw moderate success with the following singles 'Moj tempo' (My Tempo) and 'Malo' (Little). Another single, titled 'Slažem' (Deposit), was released in August. She announced her second record by releasing two more singles, 'Yin & Yang' and 'Nije lako biti ja' (It's Not Easy Being Me) featuring Serbian trap artist Fox. On 24 April 2019, she released her sophomore album, also titled Yin & Yang, through IDJTunes. Nikolija was featured on the single "Meduza" (Medusa) by her unmarried husband Relja Popović released on June 17 for his upcoming album.