can OPKs change within the hour?

Question

well i took an opk around like 7:58/59ish lol to be exact. took a picture at 8:02 and it appeared to be dark/as dark like the control line. 
then i took one around 8:40 ish or so again and it’s way way way lighter. 
what could that mean?

Answer

I got a positive ovulation today at 2pm and a negative around 4! I’m so confused too

can OPKs change within the hour?

Let’s Glow

Glow is here for you on your path to pregnancy

25+ million

4.8 stars

20+

Getting Pregnant

Pregnancy

1st Year (Baby & You)

Baby Products