Have you considered posting this in the "arachnid and other eagle scout topics" section of the forum. What you are describing sounds eerily similar to, and the time to panic was yesterday if it is, an attack and bite of a Brown Recluse spider bite.
I recommend you get your affairs in order. If you care about the family you may be leaving behind as a result of this encounter you'll want to square away the medical bills associated with recognizing the bite for what it is in its latter stages.
I recommend not returning to the hospital if it's too late. Calling on a hospice service and passing at your home is more economical and actually more comfortable for you as you'll be able to administer a "Hot Shot" and go on your terms in the haze of an opiate overdose. Be sure to let your family know and have laminated copies of your "Do not resuscitate" decision all over your home and bedroom and wear it on a bracelet and even wear it on a necklace of lanyard to ensure you won't deal with a rig full narcaine and the rush of pain that comes with the rapid onset of withdrawals.
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