A former pupil of Tain Royal Academy, Cammy had spent several years as a youth candidate with Inverness Caledonian Thistle and later with Ross County and Brora Rangers before he began playing with Dornoch City in the summer amateur leagues. In 2015, he joined Tain Thistle to play in the Ross-shire Welfare. There he earned recognition as the club's Young Player of the Year and attracted interest from new Saints manager Stuart Ross. Following another successful season with Thistle, Cammy made the step up to the North Caledonian League in October 2016 after playing as a trialist and quickly established himself as a St Duthus regular.
At the end of his first season, Cammy collected a joint award from the club (alongside Adam MacDonald) for Young Player of the Season. A natural athlete and a capable all-rounder, Cammy plays most regularly in the centre of midfield, bringing strength, stamina and a tireless work ethic to the team. In March 2018, he scored the third goal in the Saints' North Caledonian Cup Final win over Golspie Sutherland. His form earned him the club's Player of the Season award for 2017-18, and a nomination for the League Player of the Year award.
As club captain from 2018 onward, Cammy went on to lead the club to a successful Football Times Cup winning season in 2019-20, finishing the season with a season best scoring tally of 10 goals when the campaign came to an end.