When to test. My apps say two different things. Help!

Ash
Glow says my period is due on 2/26 and Ovia says my period is due on 3/1. I'm 6dpo and I'm having mild cramps, I'm tired, moody, and twinges in my left boob. I did a CM check this morning and it's the watery/creamy/lotion like stuff with something opaque/yellow stuff as well. I had a dip in my temperature today and I hope it goes back up tomorrow. Not sure if it was a possible implantation dip. 2ww is torture.