Soooo Im 4-5 days late. (My <a href="https://play.google.com/store/apps/details?id=com.glow.android">glow app</a> says i’m 4 days late and my other app says i’m 5)

I tested this morning and it was negative. When should I test again? Should I just assume i’m not preggo? I’ve had mild cramping here and there from the time i’ve been late, some constipation, moody a little and tired (I work alot so It doesnt feel abnormal on the tired part. ) i’ve never been this late so i’m all sorts of confused!

Which test is best to use?