The first few days out in the wilderness are very difficult for Sam. As he freely admits, he hasn't planned anything right, and planning your days ahead of time is absolutely essential if you're going to survive out in the wilderness. Sam has worked so hard trying to find a place to stay that he has no energy left to find something to eat. So although Sam's efforts have brought him the beginnings of a home, he doesn't have a thing to eat.
Even when he eventually finds something to eat, it's never enough. No matter how much he eats, Sam is always hungry. This is largely because the process of gathering food takes a lot out of him, making it impossible for him to restore his lost energy. No wonder he says that he's going around in circles. He keeps doing the same thing over and over again without getting anywhere, without making any discernible progress.
In his frustration Sam wonders how on earth primitive man ever had enough time and energy to be able to stop hunting for food and start thinking about other important stuff like building a fire and making tools. If Sam's going to make the most out of his wilderness adventure he'll have to figure out the answer to this question, and fast.
Further Reading