Welcome to Ask The Doctor.
I understand your concern.
You won't get sick from Hepatitis B vaccination if the vaccine used was not expired.
Very often, you get flu like symptoms and even diarrhea after getting vaccinated. This usually improves with in 2-3 days.
If this persists then this might be due to some co-incidental infection.
You would require to see your doctor in case, it persists.
Share my opinion with your doctor.
I hope it helps.
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