Hi Jumbleannie!
Sorry to hear you might have crossed into full-blown diabetes.
The OGTT is just a test to measure how well your body is metabolising sugar. It measures the difference between your fasting level and the 2 hour level after a measured quantity of glucose. In many senses, it doesn't matter where you start out, it is how well your body brings you back down to that level that is really being tested. Now, obviously if you start higher you will probably be higher at the 2 hour mark and the higher you are when you start, the less well your body will probably cope with the measured glucose. However, it doesn't really matter, because a high morning fasting level is indicative of diabetes in itself anyway (non diabetics do not have high fasting levels as their bodies are able to metabolise any glucose in their blood quickly). They have to do the OGTT as a fasting test to make sure it is only the measured glucose that is having an impact - if you'd eaten breakfast, that would be having an impact as well and would give a false reading.
The bottom line is that there is nothing to fear and nothing to feel ashamed of if you are now diabetic. All that will happen in the short term is that you will get more closely monitored (eye checks, feet checks etc etc) which is no bad thing really. If your HbA1c is good and you can manage your BG on diet and exercise, there will be no need for any medication. If that's not the case, then you can start the appropriate medication to make sure your BGs do get to and stay in a range that will help keep you healthy and complication-free.
Good luck
Smidge