Need help to know if I ovulated!!

Hi guys, I'm new to the bbt charting and I've got PCOS. I feel like the ovulation predicted in the app is not corresponding with my body's pattern, maybe cos I still can't read it properly. One day before ovulation indicated on this chart (May 17), I had really sharp pain in my lower abdomen. Not sure what to interpret of this, did I ovulate or not.. What do you think?

These were the 2 tests taken on the same day as indicated ovulation (May 18). After that all tests I took had extremely light test lines. So I'm guessing ovulation was either on May 18 or before that..