Hi, a major symptom of diabetes is extreme fatigue.
In females also urinary tract infections such as bladder infections.
At times slow healing odd sores can appear on the skin.
The feet can feel odd with numbness or tingling.
Headaches in some people when the blood sugar is soaring.
Thirst which cannot be quenched.
Itchy skin.
Unexplained weight loss.
Blurry eyesight usually after consuming too much sugar in, for example, desserts, soda pop, ice cream.
Or rice, potato chips, potatoes, pasta, popcorn, sweet liquers, beer, pretzels (simple carbohydrates) for these convert to glucose (sugar) in the body over the next hour.

You just feel all over un-well and people who know you well will probably ask you what is happening to you especially if you used to have a lot of energy and were very active and began to act uncharacteristically.