Has anyone else experienced this?

Hey ladies, I was just wandering if anyone else has ever experienced this where their lines seemed to stay the same darkness after a certain point, especially using wondfo? I’ve been testing pretty much everyday since finding out, and at first it seemed like it was darkening, but the last few days it seems to not wanna darken, but it’s not getting lighter really either. I’m paranoid but also feel reassured that it isn’t lightning. I should be 8 weeks and 5 days going by last period, but I think I probably ovulated later. I have an ultrasound set up for Tuesday at a free clinic, but won’t see my actual OB/GYN February 20th when they’ll finally send me for bloodwork and stuff.

First 4 are from the same day, the rest is one a day.