Robin,
I'm not sure if you need a referral to go to an endo (most insurance companies might need you to be referred by your PCP to any specialist docs)
As you planned, call your dr and find out why she wants to wait another 3 months. There could be a good reason. But, at least ask to be referred to a nutrionist so that you can start control by diet (to start with). If you can control it with your diet, you might be able to manage without meds. (called 'Diet controlled Type 2 diabetic)
Good luck!