PREGNANCY QUESTION! HELP!

Hello ladies! So me and my fiancé are not not trying to have a baby if you know what I mean. We just say if it happens it happens. Well I’m officially 10 days late. I have a little bit of a irregular cycle so I waited a few extra days. But I have never been this late. I took a test and it was negative: that was 3 days ago, and the test expired April 2018 so idk how accurate it was. I dont wanna get myself excited if I’m not even pregnant. Has this ever happened to anyone??? Have you ever gotten a definite negative and actually been pregnant? Helppppppppp