when Did U Get Your Positive?

I had two test done one @ 3 days past my missed period(4wks+3days) negative & another at 6 days passed my missed period(4wks+6days) dye ran so invalid, & today I went to docs & negative test & in barely 5weeks today(if I am pregnant) anyway I'm a week late & still negative test.. Anyone else like this before??  .. please answer.