Confused

Sh

So the last 3 months I’ve been ovulating on the 13th day of my cycle. Without fail, I know because I’ve been taking opk tests. But this month I forgot them at home and my bf and I were away for a few days and I had pretty bad cramps on the 13th which I’ve noticed I’ve been having them consistently that day(the 13th day of my cycle). But we got home today and I decided to take one just to see the line get lighter and what do you know it was positive. I’m just confused because I was pretty sure the cramps I’ve been feeling have been a sign of ovulation for me. Or maybe not. Idk :/