A.K.
Not usually. Generally those tests are most accurate about 3 days after a missed period. I was trying to get pregnant last year and I swore that I was pregnant but 3-4 tests came out negative. I went to the dr for an anual exam and it turned out I was 4 weeks pregnant. As a general rule though, they say that any positive test is almost definately correct, If the test is negative, try again in 5 days or so.