Low to Peak on CB Dig. OPK

Kandi
Hey Everyone! I have been testing with the ClearBlue Digital OPK's since CD 10. I have had all lows until today, CD 16 and I got a peak. No highs. Is that normal? Luckily we bd last night, and plan to again the next few nights but it's still bothering me that I didn't get any high days. I was excited for those high days. Lol This happen to any of you?