Ovulation test help

I’ve been doing these for so long and these have thrown me

Background

So I usually test from cd 9 upto around cd 18 of a 28-29 month

Last month I had a pos opk on 18th July and BFP on 1st aug. Unfort I then bled on the 6th aug and scan and bfn test confirmed a chemical on mon 12th

I read online that CD1 would be 6th aug but thought as it’s chemical best to do opks from when they arrived in the post which was 12 aug afternoon and a fairly decent line came up which by the eve had faded

I’ll attach my pics so I’ve done 2-3 a day since 12th

12th 2pm and 9pm the bottom tests

13th 7am 3pm 9pm

14th 7am 3pm 8pm the top tests