5 yr old hypoglycemia or something else?

Recently my 5 year old had a seizure and was unresponsive until we reached the ER and at that time was not fully responsive.  We have been very concerned with him having diabetes due to increased thirst and of course increased urination.  He has lost a pound in the past month and hardly ever eats.  This past Monday we had a order for a fasting glucose and Hgb A1C.  We went to have it done but since it was a holiday was unable to get blood drawn.  He ate around 9:00 but was a light breakfast.  He came home took a nap and we went to my moms for a cook out.  He didn't want to eat and wanted to play.  About a 1/2 hr. later he had a seizure.  He glucose at the hospital showed 169?  So I am wondering if his glucose dropped and then his body compensated and rose to 169?  He had what we thought was a febrile seizure about 3 years ago and at that time his glucose was also exactly 169? He did indeed have a high fever with ear infection and strep throat but this time fever of 100 which doctor didn't think that woud cause seizure.  Not sure again if it was hypoglycemia or something else?  I can still tell by his demeanor that this has affected him tremendously.  Thank you!
jrahe