confused !!!

Ashleiy
Sooo I'm confused ! Lol. Glow had me scheduled to start my period on Monday the 12th. Nothing has come yet and I am now in cycle day 31... But when I updated glow it didn't say your period is late or anything .. It just pushed my period out till tomorrow ? Another app I use Ovia said I am due tomorrow. I have been very tired and somewhat nauseous. I'm scared to test though !! I don't want to see a negative or get my hopes up. Does anyone else have this problem with glow just pushing your period out ? And or different period dates on different apps ? Thanks !! Hoping for no aunt flow !!!