A. It could be that he is suffering from gastroenteritis, he might also be experiencing some abdominal pain. I don' t think it is related to the worming, unless he had lots of worms prior to the medicine administration. I would recommend that you have him checked over. If he is still reasonably bright and eating and drinking, you can feed him a lighter diet of chicken and rice until you get him to see a vet. Remember diarrhoea can pose a serious risk if it's frequent or if it contains blood, and will need immediate attention.
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