I am sorry your boy is not feeling well. The trembling can be due to nausea. It could very well be anxiety related.
Feel all over his body for any pain response. Look in his mouth for a stuck item or any abnormalities.
Make sure he is able to eliminate normally.
Give him one quarter of a ten mg pepcid a/c (famotidine). I usually add it to a tablespoon of baby food chicken with no onion or garlic Or canned cat food.Every 12 hours.
Remove all dry food and any wet with chunks, pieces or shreds.
Feed only smooth pate canned food or baby food.
If he gets dehydrated give him tuna water drained from the can.
Please let me know how he is doing .
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