Period late

Megan
So my LMP was 12/02/15 . The <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> period app which has been on track with my period says my next period would be 12/30/15. 
Today is now 01/03/2016.
Should I be worried? Of being pregnant?