The ER vet was no help whatsoever. They just gave me the number of the wildlife place which is closed today. He seemed to do a lot better once I got him warmed up and he ate some more too. Keeping him warm seems to be key. The heating pad turned off while I was out planting flowers and he wouldn't eat. I've also been able to give him some water using the Q-tip with the cotton pulled off and letting a drop fall in his mouth which he seemed to really like. I'm going to check on the sugar water.
I just assumed he is a few days old. I first heard the babies yesterday and then found him today. He doesn't have any feathers, his eyes are closed, and he can't stand up.
Oh and he pooped which must be a good sign
Thanks for everyone's suggestions! I'm just a sucker for animals I think.