Is there a possibility?

Hey! My husband and I are trying for our 3rd baby! We’ve always seemed to miss my ovulation. It always tells me there’s a low chance of pregnancy. Since my periods have a schedule of thier own. According to my period last month I should’ve started 3 days ago and haven’t.. even tho there’s was only a 3% fertility is there a chance? I’ve tested and been negative:/ so I’m assuming I’m just late.