Ovulation test Question

MommaOf1👧🏻 • 👧🏼 1-1-17💜💕 👼🏻

So I’ve just had my first full normal cycle since my miscarriage in April and my fertile week starts today but I’ve been doing ovulation tests everyday since I stopped my period...when do the tests start to darken? During the fertile week or a few days before you ovulate? Because I’m so confused I ovulate on the third and for some reason the tests seem to be getting lighter the closer I get to ovulation.