should I be worried?

so I am on CD 19 and this is my second round of 2.5mg femara and I have not had a positive opk yet!! I took it days 5-9 which is what I did back in June and ovulated CD 18. that cycle was successful but i mc at 5 weeks. I had a positive opk 24 days after the start of heavy bleeding with that mc.

just wondering if I should worry about not ovulating this cycle or if I should relax and see what happens?

thanks in advance for any advice.