Kaleyn started rhythmic gymnastics at age 6 and began appearing in international junior competitions in 2008. She has competed in the Junior World Cup and the Junior Grand Prix events. On June 10–16, 2014, Kaleyn competed at the 2014 European Junior Championships with Team Bulgaria (together with Erika Zafirova and Katerina Marinova) finishing 4th, Kaleyn qualified 1 apparatus final and won the bronze medal in ball. Kaleyn won the all-around bronze at the 2015 Sofia Junior World Cup.