I am pretty sure there is no worse feeling in the world than that which you experience in the following scenario:
You come home from a long day at work. You had overslept in the morning, and didn't have time to pack lunch. There was something you had to finish, so you couldn't go on your lunch break to buy food. In short, you're starving.
You get home, and ravenously begin to look for signs of supper being made. Nothing. You look in the fridge, and all you see is a quarter of a piece of schnitzel from last night. Left with little choice, you grab it and devour it in two seconds flat. Looking around for more, you are forced to come to terms with the horrible realization that there is simply nothing else. It's right around then that you hear the front door opening. You peek your head out of the kitchen just in time to see your mother waltzing through the door, holding her prize: a steaming hot pie of pizza.
Picture yourself in that scenario. Now tell me, isn't it true? There is no worse feeling in the ENTIRE world, huh?