WOW, I just read a pharmacist study that found that only 16% of HPTs actually detect pregnancy on the 1st day of your missed period. First Response Early Result was the only one that was consistently accurate, sensitivity to 6.3 mIu.
Also, the study found no false positives. None. A line is a line. No test registered a positive with the null sample.
Also, I just got a LINE! On a Dollar Store test ... but it disappeared. :( But a line is a line!