Guy you mentioned black bumps on tail/ this guy could have a bacterial infection, or before you get him to vet, do something for me, take a moistened q-tip even take some of the cotton off leaving a more firm tip and rub it over one of the black bumps not hard but... with some pressure, see if it lifts off, may take a couple times if rubbing it. Just try and see if it lifts up.

Before you get him to the Vet you are indeed going to have to hand feed/hydrate as I said to keep his strength up or you will loose him. Remember small amounts but more frequent, be careful not to choke him.
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PHEve / Eve