Super confused....please help.

Okay so I had a chemical last month and my doc said there’s no need to wait to try again this month. It’s my ovulation week and I’m getting negatives. I took one this afternoon and it’s more weak than the ones I took previously and it’s 2 days away from my ovulation date. I ovulate pretty regular so this is weird. Also my cervix isn’t high it’s low. But it’s still soft and open. I’m just wondering if anyone else has gone through this at all. I would really like some light put on the subject. Please help.