Clear blue opk?! So confused 🤔

For those who have used the CB advanced opk tester, the one with the smiley faces.... I have a question. I’ve tested since Monday and have gotten the “O” for low. And this morning I got a solid smiley for my “peak”. How did I just skip the high fertility period with the blinking smiley? I feel like something isn’t right?! I mean imma go at it today & tomorrow but still it’s weird or no?! This is my first cycle using this thing lol I usually use the cheap opks and just compare them.