Need help with opks!! 😩

Ladies I am desperate for help!! I am sorry for the long post, but I am seeking advice/personal experience about opks...

I started opks this month on CD 10, taking them twice a day (2 pm and 11 pm). I had 2 positives on CD 10 and 11.. then yesterday, they were negatives (CD12), but the test line was SO close to being the same to the control line, I wasn't even 100% sure the 2 pm one was negative, but the 11 pm one was for sure. Then, around 3:30 today (CD 13) saw eggwhite cm, so tested again to see and it was positive!!

What is happening? My bbt has started rising slowly, but so spike, I thought I was around 2 dpo but now, I am not sure I even ovulated! And I know I don't have pcos (had ultrasound done a few months ago after mc and no cysts were found + had my hormones tested).

Has anyone ever experienced something like this? This is my first month using opks and charting, so maybe I am doing something wrong?