When to start opk when on clomid

Jami

This is my third month on clomid. I am currently on cd17 and I take clomid from cd 5-9. I was using just this app to predict my ovulation period, however, I didn’t get pregnant. I have been starting my period around cd 25 the last couple months (normally I’m not regular which is why we are using clomid). I started taking OPKs on cd 11 and have yet to get a positive. Should I be worried I’m not going to ovulate this month? Or is it possible I just haven’t ovulated yet? This app predicted cd 15 for peak. Picture for reference of my opk (2 each day).