Are false negatives a thing? Late for my period. Wonfo new ones?

A❤️C

I'm on birth control and take on the regular. It's highly unlikely I'm pregnant because we don't even have sex that much right now 🤣. But why when I went to check my app to see when my period would start it's late? By 1-3 days. Usually the app is off by 2-3 days. So I usually start 2-3 days before the day of my period. Welp. We are one day 1 of my period on the app which is VERY weird for me. I took a wondfo and it's negative. But wondfo just made new tests and look at the reviews it talks SO much about not being sensitive and get false negatives or not getting a positive until way later vs other tests. Anyone had this happen? I'm overly worrying. I have a 8 month old so don't exactly want to be pregnant and probably done having children otherwise.