have PCOS it’s hard to tell if I’m ovulating.

I took farmara this month and my doctor wants me to use opks I got a positive today is it to late to do my trigger shot? Or how does it all work on day 12 of my cycle I had 2 follicles 14 and 13.5mm today would be day 16. I already bought my trigger shot I’m just wondering if I should take it since I just got my first positive opk or is it to late? I’m using the digital clear blue and I got a smiley face. I think I ovulate the next day . I dunno I’m so new to all of this. Any fees back would help.