Ugh. B-HCG Mix-up at the Worst Moment

Patient A is being seen in the ER for a likely 16-week miscarriage. As you may know or suspect, it's not a pleasant time for the patient, the family or the doctors.  Bloody sheets and disappointment fill the room.  Next to a heap of bloodied clothing sits a three year old little boy looking on nervously while pretending to color.  He's wearing one of those kid leashes which appears to be tied to the chair.  The doctor comes in and examines the patient, chats with the little boy and then leaves the room to order a B-HCG test.  Some time later, a lab report is printed for a different patient down the hall. Her B-HCG is negative. Curious, I ask the doctor about it. In the rush of a typical ER moment, he assumes we are talking about the patient having a miscarriage. Not realizing we are on two  very different pages of possibly different books, I say nothing and just ponder what in the world he's talking about.  About this time, the miscarriaging woman's husband is walking by the desk.  The doctor stops him to inform him, "Your wife's not pregnant. It appears she never was."   The room is silent for a moment-- or maybe the voices and background noise just blurred into that slow motion gargle seen in movies. The husband is very bewildered upon hearing this strange news. And for a split second you know he wonders if his wife has feigned a pregnancy. Could it be?  He asks, "What do you mean? How can this be??"  The nurses and I are sitting behind the counter wondering the exact same thing but we all appear to be stunned. No one says anything. We all exchange glances and mouth confused, "What?"s.  The doctor continues on, "We have no idea, but there's no record of a positive pregnancy test ever. She's not and has not recently been pregnant." The husband goes out into the waiting room while the doctor goes into the charting room to talk to the ultrasound techs. Suddenly it's occurred to me what's happened. I feel overwhelmed with guilt. I somehow must've confused the doctor into believing the B-HCG was negative on the wrong patient! Thankfully it all got fixed in the end. Unfortunately, the patient having the miscarriage had indeed been pregnant, and the patient with the negative pregnancy test also had a positive meth test (see below).