Please help (OPK question)

Last night I took an opk and it was negative but it was really dark and seemed as though I was close to ovulation. Well tonight I took another opk and it’s faint again and way lighter than the test I got last night that looked like I was going to be getting a positive today. Did I miss my positive? I took a test at 10am and it was super faint. I’m just confused. Like how could it get dark and really close to a positive and then now a negative?