Someone Help Please

My cycles are regularl i get af every 28-30 days i THINK. And i have endometriosis as well so i pretty much know when my periods are coming because i PMS extremely bad starting the week before AF. That being said i usually know when i ovulate as well because i get cysts on my ovary and cm but this month i wasnt paying attention so i have no idea if i ovulated when glow says or if i ovulated late. Whats the latest i can ovulate? Starting maybe about 5/6 days ago i was having twinges/ mild cramps and the last 2 days i had white lotiony discharge that was leaky. But we did BD on the 6th 8th and again on the 22nd. I tested yesterday night and got a BFN on a dollar tree test. AF due today and I’m not having any of my usual bad PMS. No sign shes coming today just some lotiony discharge still which im usually dry when she comes. Could i have ovulated or implanted late? Could i still have gotten pregnant this month? Keep getting BFNs😫