Hey ladies

So I have a quick question I have been tracking with opk since the day after af .. which ended on the 29th on the 4th I got the first picture displayed at the bottom which was darker than my other tests so I continued to track every day twice and the 5th they looked the same and every day since the fifth they have been lighter than the one on the 4th may I have ovulated in the 4th even though my test isn’t as dark as they say it usually is because i don’t understand why they would get dark then light again

opk from the 4th

opk from today