I am not a doctor but I believe you are in desperate need of insulin injections. The hospital won't let you leave until your blood sugar is under 300. Anything over 300 is really dangerous. Over 500 you are at great risk of falling into a diabetic coma and never waking up. This happened to a friend of mine who was only 24 years old. Please seek help now and not wait until July. If your sugar is that high again go to the ER asap. Best wishes.