I would definitely go to see a doctor. If it is type 1 diabetes, you would do exactly the wrong thing by giving him carbs (such as cereal, juice, toast etc.) right now and diabetes is so simple to check and you should not sit at home and worry that that's what it could be. I hope it's not what you think and I hope he will be fine and it was maybe just a minor cold/flu, but I'd want to be on the safe side. IF diabetes is the diagnosis, maybe look at the Diabetes Association Website as a resource as well. http://community.diabetes.org/n/forumIndex.aspx?webtag=adaindex
Good luck, Nicki
Also, he has had 2 bed wetting instances this week (something we've not had in probably 6 months or more as he was a very early potty trainer). So this adds to our concerns of diabetes?