At fourteen I married My Lord you, (7)
Notice how, at the age of fourteen, the wife considers her husband to be her noble lord. However, as she matures even just over the following year, the wife develops a more sophisticated understanding of the equality and sharing in their relationship.
Called to, a thousand times, I never looked back. (10)
At this moment, the wife may be refusing the husband's affections because she's uncomfortable with her new identity as a wife, with a "Lord" for a husband.
At fifteen I stopped scowling, (11)
It seems that, now that she's fifteen, a year has passed in which her desires and affections have, let's say, "blossomed."