What does it mean when you have a very small appetite, over eat often, and don't feel hunger sometimes?

Need more info : Lack of appetite can have many causes. You gave no information about yourself, so I cannot answer your question. I can say, however, that causes range from loss of smell, to problems in the GI tract, to depression, to chemical and hormonal imbalances, infections, cancer and more. Hope that helps.

Depends: on your overall nutritional state. While diabetes, thyroid, mood disorders, pregnancy and other medical causes can be associated with appetite changes, a disconnect between signals (hunger) and eating behavior is typical in the obese (S. Schacter research... half a century ago and always found to be true).