BBT drop after I thought I had ovulated - help!

My advanced opk reached Peak on CD22 after lots of days of High and yesterday FF put crosshairs on my chart marking ovulation at CD23 which made sense and I was quite happy I had timed BD well as I got O day and O-1. That was until my temp dropped this morning so the crosshairs are gone. I only had two days of barely egg white which coincided with the peak days on opk (clear blue dual hormone one) and I have creamy CM today so I'm wondering if I have ovulated yet or the opk was wrong! If the opk was right then I would be 4DPO

Any thoughts gratefully received :)