How long for a positive after missed period?

Hi all, my period is now 3 days late but all tests are negative. I swore this mornings had a incredibly faint second line but honestly I think I was just making it up in my head 😂

My question is, how long after a missed period did you finally get a positive test? I’ve had cramps for 5 days now, and keep expecting to wipe next time I go to the toilet to find its started but still nothing.