Positive?!

Brittany • Chloe Elizabeth 7-30-13. Sophia Grace 10-15-15. Baby #3 09-20-16
I took this today (according to to different apps I'm either 6 or 7 DPO) and it's very faint. I'm not sure when I'm to expect my period as different apps are saying different things too. Should I retest in a couple of days? Is this a faint positive?