So I've been using OPK's this cycle since my OBGYN recommended them. I was lucky and got the ClearBlue Digital Advanced for a great price. According to it I received my solid smile (peak fertility) on Tuesday, but I had a follow up doctor's appointment on Tuesday during which they did an ultrasound and said I should be ovulating any day. So confused I went out and bought the trusty First Response Simple Ovulation Tests. Below is a picture with the dates and times of the tests taken. As you can see I have marked one I think was faulty because that line was definitely darker today. Thoughts?