RE: YOU KILLED, NOW WHAT?
Your concern now is to get that meat cooled as soon as possible.
After you dress the deer out and haul him back to your truck, you have a couple options:
Call a butcher and get him in cold storage.
Pack the cavity with as much ice as possible and butcher the deer tonight.
I would skin, cut up the deer and put the meat in the frig. Don't worry about slicing, wrapping etc, you can do that in the next few days.
I would not chance hanging the deer out overnight, even if it's packed with bags of ice.