Others have addressed most of this, but no one else has called this out specifically: "my" is not a pronoun. Pronouns stand in for nouns. "my" stands in for a d

Others have addressed most of this, but no one else has called this out specifically: "my" is not a pronoun. Pronouns stand in for nouns. "my" stands in for a determiner. Both replace concrete with relative, but that's a semantic category that doesn't impact syntactic class.