AF is 3 days late; all tests have been negative

I’ve been lightheaded and had several other more mild pregnancy symptoms. My period has always been extremely regular, but I only went off birth control four months ago and had an early miscarriage three months ago (this is only my third cycle since). I’m leaving town for an extended period of time later this week, and just want to know for sure whether I’m pregnant before I go because it will impact my activities drastically.

Any advice?