The wedding at Cana JHN 2:9

During a village wedding feast, the wine ran out, an embarrassing problem for the host family. His mother told Jesus, and after water was poured into six stone jars meant for washing, what was drawn out turned out to be wine, better than what had been served first. John calls this the first sign Jesus performed.

Cana was a small village in Galilee, and the detail that this is a village wedding explains why running out of wine was such a serious embarrassment, a lasting shame for the family hosting. The ordinariness of the setting is part of the point: the first sign happens at a modest family occasion, not in a temple or before crowds.

Those jars were used for Jewish ritual purification, that is, for washing before meals. That they are filled with water and end up yielding wine better than what came first highlights the contrast between their ordinary use and what happens that day, without the text explaining the change any further.

Readers can take 'my hour has not come' as a flat refusal, but Mary does not treat it that way, since she still tells the servants to do whatever he says. Christians differ on the tone of this answer, a mild rebuke, a plain statement about timing, or a question, and on Mary's role in what follows, and the text itself does not settle the matter.