 Heimer got his first team debut for B93 on 6 June 2015 at the age of 17 years, 5 months and 27 days, making him one of the youngest debutants in the clubs history.After over 70 first team games for B93, Heimer left the club to join Thisted FC in January 2018.After a year at Danish 1st Division club Thisted FC, Silkeborg IF announced on 30 January 2019, that Heimer had joined the club on a contract for the rest of the season.