This is my first cycle using Clomid 100 mg which I took days 3-7. Started using clear blue advanced digital ovulation tests on cycle day 12. Got low fertility, then high fertility for 5 days, then today (cycle day 19) I got low fertility (I used a different test stick holder that I had from a previous box).  No peak! SO frustrating. I've been using these ovulation tests for the past year and a half and I have gotten a peak (I may have had 2 or 3 times when I didn't get a peak). Doc said to bd every other day from cycle day 12-20. Which we have done.  I guess the rest is out of my control, just getting so frustrated!