I am so scared not to be satisfied

Hunger is a natural feeling, just like eating is our most basic and natural behavior. You shouldn't afraid from being hungry as well as not feeling ashamed for eating. I believe that you should get an advice from a professional as you might suffer from an eating disorder. It is important that you take care of yourself at this point, not eating isn't the solutions. There are many experienced professionals out there that can help you with your fears and self anger. I think that telling what you had just wrote in your question to a friend, parent or a doctor would be a great step towards solving your problem.

Why are you so worried about eating a big dinner?  In many traditional cultures, dinner is the biggest (and sometimes only) meal of the day.  The 3-squares-a-day approach came out of the Industrial Revolution, but there's nothing natural about it.  It is far more natural to eat less during the day and eat more at night.

If you worried about eating too many calories in general, then you should focus on what types of foods you're eating.  Check out: www.thepaleodiet.com