She carded rounds of 71 and 65 to finish a single shot ahead of England's Alice Hewson and Finland's Matilda Castren, and in the process jumped into a tie for second place on the European Ranking behind leader Agathe Laisne.

[3] As a result, Thomsen played for Team Europe in the 2015 Junior Solheim Cup held at Golf Club St. Leon-Rot in Germany.

She shot an all-tournament best 8-under par score of 64 in the final round to win the French International Ladies Amateur Championship ahead of Alessia Nobilio of Italy.

She was a big part of a star-studded group of freshmen in the Florida State Seminoles women's golf team that included Frida Kinhult, Caroline Hodge, Amelia Williamson and Beatrice Wallin.

[4] By May 2020, she couldn't even walk, and decided to undergo the same operation as Tiger Woods, a surgery designed to stabilize the lower part of her back.