Testing after embryo transfer?

I transferred 2 frozen embryos day 5 in May 3rd, currently I’m 6DPT,

When did you test and got your positive?

I have 1 digital test left i was thinking of testing at 7DPT but I’m afraid of getting false negative and waste a test but i want to test sooo bad,

(By the way when i did a 1 fresh embryo transfer i tested at 9DPT but not a digital test and i got a very strong line )

Also i read this