Good luck.
I was also young when got married, I do remember when we got married but neither I nor my ex recall when we got divorce. We had to obtain it from somewhere as we needed divorce decree to be able to remarry. But I to this day we don’t remember and have to dig it out. Some things just don’t stay in ones memory
I actually think if it was annulled you don’t need to put it down. Annulled is same as never married