I felt hungry suddenly yesterday &kept eating &food didn't curb my appetite. today i am feeling irritated &depressed &down. i am not expecting my period anytime soon and i am not sexually active for more than 6 months. why am i feeling that?

High and low: blood sugars can cause these feeling, even depression is more common, if you are insulin resistant/carbohydrate sensitive. Testing for insulin resistance with your doctor is useful. Curbing consumption of bread, pasta, rice, potatoes and sugar, may help.

Calories: Feeling irritated after eating a large amount of calories can cause an insulin surge and that can cause hypoglycemia and that could cause irritation, depression and feeling down.