When to test?

Dakota • TTC baby one since November 2014
So for some reason glow isn't predicting my period. For the last two months it just tells me to log my period. I'm on CD 24. Last cycle was 25 days and the one before that was 29. But it predicted my period on the 29 day cycle and I was 5 days late. So I guess I'm having a little bit of irregular cycles?