For clarity's sake, are you defining a teenager as someone between the ages of 13-18? Because in the 1500's they were considered an adult at this age.

In medieval Portugal, like the rest of Europe at the time, most of the population would be involved in some form of agricultural work. People could be serfs bound to the land they worked or free farmers that rented the land from its lord, or rarely those that both owned their land and actually worked it themselves. It is also worth noting that at least in the nobility girls would likely be married off during that age range, although I don't know if and how this differed in the lower classes.

I'm not at all an expert, and hopefully someone with more detailed knowledge will write a more comprehensive answer.

Source: Daily Life in Portugal in the Late Middle Ages by Antonio Henrique R. de Oliveira Marques.

As a follow up question, would the same be true for a boy?