I am diabetic to and have had the same thing happen. With insulin you usually buy it a vial or more at a time. It isn't possible to buy 2 or 3 days worth in many cases, and if you have to pay for it without the discount the insurance companies get, it is expensive. I actually spoke with an insurance representative once when in this same situation and told her if I die this weekend while you are straightening out this problem, expect a huge lawsuit that will make a vial of insulin seem like a dollar. Didn't change her opinion a bit.