Sick rooster. Any ideas?

We have a 18 week old black silkie rooster. We adopted him a week ago. Tuesday morning he was fine and crowing. Tuesday evening and wed morning my son noticed that he was tilting his head alot, worse on Wednesday am than Tuesday pm. Unfortunately, being 12y and new to owning chickens, he didn't recognize that this should be reported to me. Last pm when I went to the coop, our roo was under the roost. When I picked him up he was twisting his head severely even to the point where his head is completely upside down and walking in circles or backwards. After reading on here, I gave him 15 mls of plain pedialyte and some poly-vi-sol, put him in the infirmary cage outside the coop but where they can still see each other, and tried to clean his right ear with 1/2 strength H2O2 because we noted that the feathers over that ear were matted down. This morning he was alert but neck/head seemed about the same. Took him to the vet this am. His temperature was 108. She gave him subcutaneous fluids under his wing and Excenel 50mg subcutaneously under his other wing and I am to give the Excenel daily for 4 more days. When we came back from the vet he ate some chick crumbles mixed with water. I put a small plastic box lined with towels for him to lay in because I thought it would help for him to have boundaries, otherwise he seems to back into the corner of the cage or wedges himself between the waterer and side of the cage thus making himself wet. The only other time he seems totally relaxed is snuggled up in my arms with his head on my chest. Any suggestions for what this might be, other than an ear infection or anything else I should do? Oh and he has pooped a small amount of normal poo this afternoon.

Sorry about your silkie cockerel. Was he vaccinated for Mareks disease? Several things can cause wry neck (torticolis, crook neck) which is what he seems to have. Diseases such as Mareks, avian leukosis, serious infectious diseases such as fowl cholera, coryza, and others, vitamin deficiencies, and most commonly, head injuries. Silkies sometimes have a vaulted skull that can be easily damaged. I would keep him separated close to food and water, keep down noise and other stimulation, and make sure that he is getting enough to eat. Some wrap them in a towel and help them to eat by putting water into the feed to make it easier. Poultry vitamins including vitam B1 (thiamine, vitamin E, and the mineral selenium are given to treat this.Poultry Nutri-Drench and Poultry Cell vitamins contain all 3, but you can use other brands in the water, and give some egg, tuna, salmon, chopped nuts or sunflower seed in small amounts for selenium. Here is some info about wry neck:
http://www.browneggblueegg.com/Article/Crookneck/Crookneck.html
https://www.backyardchickens.com/t/97121/lets-talk-wry-neck-crook-neck

Thanks for the info. Yes, he was vaccinated. Wondering now if he has a brain injury from one of the other chickens.