I have a faint positive...but doctor is testing -

They sent me for blood today because they kept saying "it's a false postive"...but this is my 3rd postive on three different tests since 11dpo. All faint but clearly there, right? 
They also claimed I'm not due for my period yet because "it hasn't been a month". Last I checked women don't get their monthly every 30 days exactly. I'm on a 27 day cycle and was due yesterday.