Ovulation Tests

I read a study recently on CNN that showed most of the ovulation tests on the market would not show a true positive ovulation test. Keeping that in mind, I'm trying to decide when I ovulated, and I think it might be the 29th. I know it's not truly positive, but I think maybe I'm not going to show a true positive amd i also had some twinges that day. Anyway, I thought I'd ask everyone else what they thought.

I know I didn't miss my surge because I've been testing 3 times a day at least for my surge. I only saved 2 tests per day to show myself the progression.