My child has food poisoning

We went for a family Sunday lunch last weekend. My daughter ate the kiddies platter for 1 which had mussels in it. within 30 min of arriving home she had fever with stomach cramps. Then the vomiting and diarrhoea started and lasted throughout the night. We ended up taking her to the ER for fear of dehydration. she was treated at the hospital and spent 3 days recovering at home. My daughter who is 9 yrs old is too afraid of ever going to OB again.