Ovulation

I just used a Clear Blue Advanced Digital ovulation kit for this month. Last time I used one before my IUI, I thought that the flashing happy face meant peak fertility, and I booked my appointment for insemination. It didn't work and I had a mental breakdown. So this time around, I decided to get a 2 month supply and do a test run. Glad I did. I started testing on day 6 of my cycle, per directions. On day 8 of my cycle, I started showing high fertility. That was last Thursday. Today, I finally got peak fertility. 6 days of high. Is that normal?