Late period / negative tests

Bethany

I am currently late by 5-6 days, sore breasts which is not a normal pms symptom for me. Taken a few tests and all came back negative. How long after a missed period should it take to get a positive? No reason why I should be late I have a normal cycle of 28-29 days every time. Has anyone had a positive test after this long? I’m going crazy!