Ask your doctor to test you for it.
Talk to your doctor. He will do a fasting blood sugar or an A1C which measures the average blood sugars over a period of a couple months. The most common symptoms of diabetes are excessive thirst and urination, sometimes increased hunger, fatigue and sometimes weight loss. However, many people don't have any symptoms at all until it is quite advanced. You could also be found to have pre-diabetes which means you are headed in that direction and is a good opportunity to make some changes and slow the progression.