What's the chance?

Before y'all call me crazy I have been reading stories on here so that's why I'm even asking this question. I probably shouldn't even be asking it.

Soooo I've taken 6 HPT's over a course of three months. All neg. but just to be 💯 I got a quantitative blood test. The result was less than 1 count of HCG. This was about, idk, two and a half months after I got down and dirty? I don't remember the exact date.

What's the likelihood that these were all wrong? I've gotten withdrawal bleeds too but I've been seeing a bunch of crazy stories on here and other websites