Ovulation Test? Pregnancy?

Okay, so I’ve been monitoring my ovulation as I am nursing and taking the mini pill (Nora B) and DON’T want to get pregnant. We had unprotected sex Monday night. I took two ovulation tests Monday, and I had like no second line. I took one Tuesday morning and had like no second line. Again, so no ovulation. This morning I took one, and it looks like a positive ovulation test. (I think I may have put it in urine a little longer than I should have) I took another one a few hours later, and again, back to a faint line. I’m so confused. When trying to conceive our son, my line progressively got darker, ovulation occurred and had a positive ovulation test for two days. So I’m not sure if the positive ovulation test is a defective test, or if anyone has had this happen? Thoughts.