how does macbeth feel about what his army has done while the army in dunsinane prepares for battle?

Most of his army has run away. They know that Malcolm and the english force are coming. Malcolm, Siward, Young Siward, Macduff, Mentieth, Caithness, and Angus march toward Birnam Wood. As they approach the forest, Malcolm instructs the soldiers to cut off branches and hold them up in order to disguise their numbers.This will look like the forest is moving towards the Macbeth's castle.