Hunger occurs for many reasons. Some people think they are hungry when they really just ate a big plate of food. That can be because of the situation, things that happened during the day, how you feel or what you ate. Some people get tired and then find that they get hungry. Sometimes, when you are tired, that is because of other reasons like dehydration or other factors which then may lead to hunger.
Stress causes people to be tired but then you start thinking about food. Your body or brain thinks that food will bring you energy. So, your body tells you to eat. When people are tired, they are relaxing and resting. They may then get bored and start thinking about food. At this point, they get hungry.