If you are diabetic you really need to take care when cycling because it depletes blood glucose levels quickly and that's probably what happened to you. If you are going on a longer ride you probably want to keep a candu bar with you, you could consider carrying some of those gatorade prime chews that will give you 24g of carbs in a pinch.
All of the symptoms you gave us are symptoms of hypoglycemia so it appears you need to better manage your diabetes while cycling.