Can a pregnancy blood test give false results? My period is 7 days late and I got a positive pregnancy test at home but took at STAT blood test at my doctors office and they called me back telling me it was less than 1 so negative. I have no period, my lower back has been hurting, I have an achy feeling in my belly, and have been having headaches. My period is never like this and I have a calendar making sure I know my dates. My period is every 30 days on the dot. Help

There can be false-negatives when getting a blood test but its much more likely that the home pregnancy test was giving you a false positive.
Its hard to say based on symptoms alone but backaches, cramping and headaches are commonly signs of PMS. Even if you haven't experienced it before, each cycle can be different. If your period hasn't arrived in another week, contact your doctor to get another test.

False positives on a HPT are pretty rare... not to say it never happens, but they are rare. Depending on the blood test the doctor administered, it could have produced a false negative, which is common, I agree with Learning's advice above. Wait a week and then retest. Good luck.