This just happened to me a few weeks ago. The fertility clinic thought I'd missed it. That can happen if you don't do at approx the same time every day. They have me test between 10:00am and 15:00. I'd done everything I was told to do. So they did an ultrasound. Even with clomed, I hadn't ovulated. I had a follicle on the left side waiting. So they gave a HCG shot to take that night at 11pm. The next day I had a positive OPK for the following day. So I had IUI two days after the shot. I hope my experience will help. So yes, it can mean you still have not ovulated. But you might still. Baby dust to you!