Queen Elizabeth II is your Head of State. If I'm a subject then so are you.
However, by law I'm a citizen, not a subject. I just don't know how the law stands in Canada. You Canadians could be subjects, but we Britons aren't.
You are the one who claims to to be a subject.
I claim NOT to be a subject. Because I'm not.
Apart from Her Majesty Queen Elizabeth II. You may think that Canada is a boring republic, but then the reality is rather different.
and I'm not part of an Empire.
You're part of the British Empire. PC speak may deny that the Empire no longer exists and that Canada isn't a part of it, be we all secretly know that the opposite is true.