A blood test on you cant hurt a baby. Many pregnancies end in miscarriage. A blood test wouldnt cause that. The timing would be coincidental. If the HCG was low then it's likely it was a chemical pregnancy, a term given to pregnancies that end before a heartbeat is detected. It's sad but it's noone's fault.
The other way to confirm a pregnancy is wait. Back in the day, women were advised to wait until they'd missed 2 periods before confirming a pregnancy. It depends on what model of antenatal & birth care you'd prefer. Private OBs book out fast - like 5/6 weeks pregnant fast. It's not such an issue with public hospitals, depending on where you live.
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