So confused

So I’m three days late and I took two tests this am and both came back negative. I’m almost always on time if not a day early so three days late is unusual. My husband and I have been trying since November and I was so hoping to wake up today and get a positive. I’m a night shift nurse and I had a terrible schedule last week and I was exhausted all week. I’m starting to think my body was just under stress and that’s why I’m late. Should I wait and take another test tomorrow if I don’t start by then? I just don’t know what to do.