Ovulation Tests, please help

Chantae • IVF ROUND 1: Angel baby 19/04/21 ❤️ IVF ROUND 2: FAILED 💔 IVF ROUND 3: Angel baby 22/10/21 ❤️

How quickly can ovulation tests go back down? I got my peak at 4pm today and just now the line has gotten fainter...