I'm so sorry Kodah is not feeling well.
The symptoms you describe could indicate various conditions. If he spends time outdoors, he could have ingested a toxic substance like a plant or flower, lizard, toxic toad, insect, bitten by a venomous snake, etc., depending on your location. This also could have happened indoors with the ingestion of cleansers, getting into the trash, houseplants, being bitten or stung by a venomous spider or insect. You might have dropped some medication, and he ate it.
He also may have developed an infection in his system, which is causing shivering, due to a fever, drooling due to nausea or a dental problem and lethargy, due to not feeling well at all. There is really no home remedy for this, because we don't know what the cause of the symptoms are.
Because of his young age and the symptoms you described, it would be advisable to have him seen in person by a vet, immediately, so you can get a definite diagnosis and he can be treated before he worsens. If your vet is closed now, take him to an ER vet center.
I hope all will be well with Kodah and please let me know how he's doing and what the vet's findings are. Thanks!
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