Give me reassurance

Arden

I have 3 <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period apps</a>. One said I was meant to start my period 2 days ago, one said yesterday, and one says tomorrow. So far I haven’t started. I’m hoping that I’ve just made a mistake with one of my apps. Someone please calm me somehow?