Our ceremony is technically a convalidation which I did not understand until recently.
Here is an excerpt from the most straight-forward explanation we found:
What does it mean to Convalidate a Marriage? We probably all know at least one couple who was not married according to the requirements of the Catholic Church.
It is not unusual for such couples to later wish to have the Catholic Church formally recognize their marriage. Convalidation is the process by which the church recognizes a marriage that did not previously meet the requirements of church law. In a simple validation process a couple in a stable marriage participates in some form of preparation, and then they sanction their consent “I-do” in the presence of a priest or deacon and two witnesses.
From:
Marriage is one of the oldest sacraments
Published July 18, 2003
The Catholic Mirror
By: Deacon Dennis and Sarah Luft