Peak opk, then negative day after?

So yesterday I took a clear blue advanced opk. I bought them the day before, took one, and it said negative. Took one yesterday, it showed peak (my wegmans brand did too). I also had ewcm yesterday, so we made sure to bd. Today I took a wegmans brand test and it was more faint than I expected it to be, but they had been getting stronger previous to yesterday. Is it supposed to be lighter the day after a positive? Gonna bd again today, but was just curious if anyone has ever experienced that with opks. Thanks!