Question on Ovulation Test

I am about 3 months TTC and I’m getting confused with the lines and I am reading them backwards I think 🤔 ok so there is a T and a C which line needs to be darker for your test to come back positive? I took one this morning and it looked very positive to me but yesterday I think I messed up and had it flipped around ( that probably makes no sense but I think I’m reading them wrong)

The top two tests are from yesterday

And the bottom two are from today.yesterday the T on the white test was nearly not existent then the one at 6pm on top( yesterday ) shows the C line dark and T line light? Then today they are both dark. So any help on this would be appreciated. I’m using the calendar on this app but every time I put in my ovulation tests results the ovulation days change and it starting to stress me out because I’m not truly understanding how all this works. When your a positive for ovulation are you “ fertile “ for a couple days AFTER the positive or is my chances of getting pregnant higher before the positive ovulation?Sorry for the long post I’m just truly confused 🤷🏼‍♀️ 😭

Thank you so much