The only similar marriage that I can see on Scotlands People is a marriage in Stirling of a Thomas Cannon to Bridget Hannachan?? or possibly Hennachan??(the name is difficult to read) on 20 Oct 1891 which does seem possibly too early. She was 19 and he was 21 and (her parents were listed as Thomas and Bridget nee Cassidy). This could be the family in 1901 living in Broad St, Stirling
Thomas Cannon 30 b Doune, Perthshire Plasterer's Labourer
Bridget Cannon 27 b Stirling - Fish Hawker
Francis Cannon 9
John Cannon 7
Bridget Cannon 5
Mary Cannon 5 Mos
Kay
Edit - Relating to one of your previous posts which I replied to - Is Bridget's daughter the Susan Canon who married Richard Napier Fleming in 1929 in Stirling ??
The marriage to Richard lists her as 18 and the child of Thomas Cannon (deceased) a Plasterer. The mothers name is hard to read and looks like Betsy Heneghan - Presumably spelling of the surname does vary