Timing of ovulation with opk

I am a little confused as what to count as ovulation day... I was testing with both clearblue digital opk and strip tests. On the 14th I got a solid smiley with clearblue (also had ewcm) the 15th & 16th I got a positive on the strip tests then the 17th it was negative... should I count ovulation 24-36hrs after my first positive with the digital or 24-36 after my last positive on the strip test? So 1dpo would be the 18th?

I also went for bloodwork the 21st and my progesterone was 11.9 which doc said indicated ovulation.

I’m so confused 😐