So confused .. Has anyone experienced this?

Long story short: this is round 2 of 150 mg of clomid. Today is cd20. I got a smiley face on an ovulation test at 9:00am for the first time this month..Well, at 7pm I just randomly took another and it had the empty circle meaning the surge is low. So has anyone ever experienced this? I've been testing since cd12 so I know I didn't miss a day of smiley or anything. So discouraged that I didn't even ovulate AGAIN this month. 😰