Thank you guys for all your advice

The regular reptile vets were unavailable yesterday but I was able to get him an appointment with our local emergency vet who I was unaware saw reptiles when I posted this. Cecil will be receiving injections of Baytril (I think is what it was? I'm at work and can't read the label atm) every 5 days for the next few days. I'm glad I found someone to see him.

Thankfully he is my only snake so I have no others to worry about catching his infection. I've uped his humidity and will see what I can do about the ambient side of his cage. His warm side fluctuates between 89 degrees and 94 degrees but typically stays between 90 and 93 degrees (sometimes reaches extremes because of ther most at but never less or more than what's listed above).

Thanks for the advice everyone, hopefully he'll be back up to speed soon!