HELPPP!!!! When should I take a test?

Althea
My boyfriend and I had an oops and according to this app I am currently 1 week and 3 days but I know from my previous pregnancies that I'm not techniqually pregnant yet because my egg isn't fertile and I'm not sure when I should take a test to be sure since the 2 times I was pregnant I didn't find out right away with my son I found out at 9 weeks and with my second (medical miscarriage) I found out at 3 weeks I was pregnant up till 6 weeks with my second any ideas when I should test or should I not worry about it till later on?? I mean he is very potent I got pregnant both times on bc and now I'm on no birthcontrol so when should I take a test to be sure