I was hoping it was his allergies but it seems to be something more serious. Apparently on top of his lethargy he is running a fever, he has dropped weight and is a bit dehydrated. (Not surprised at the last one...he hasn't wanted to eat or drink all weekend.) He also hasn't been doing a very good job of grooming himself for over the past month...(I wasn't too worried about that one since I had planned on busting out the clippers in a few weeks.)...but it's indicative of something more than just a bug over the weekend.
So...they are keeping him today and overnight to observe and will be running some bloodwork on him to see if anything shows up there.
Sigh. I hate being at work and not having him here.