The feeling of relief he had up until a while ago had disappeared in one go, and Shin once again lay down on the ground.
He didn't feel like getting up, and he worked only his mind, but no matter how much he thought about it, he couldn't come up with an answer.
(It's no good, huh. In these situations, I should empty my mind for a little.)
It was Shin's way of calming down when the inside of his head was a mess. When there was something he couldn't understand, he'd temporarily let go of everything, and then rebuild this thoughts.