This is my first time using an opk this month so I’m not sure what is normal and what isn’t. Glow predicts my ovulation date as the 25th and I think it is pretty accurate from tracking my CM in previous months. Is it normal to still have a very faint line on my opk if I’m only 4 days away from my O date? Shouldn’t it be getting at least a little bit darker? Thank you in advance!