Pip is horrified when Magwitch shows up in chapter 39. He is shocked and upset, first, that he owes his wealth to a man he regards as a criminal lowlife. (We might feel the same if we found our wealth came from someone running a pornography site.) Second, he realizes...
Pip is horrified when Magwitch shows up in chapter 39. He is shocked and upset, first, that he owes his wealth to a man he regards as a criminal lowlife. (We might feel the same if we found our wealth came from someone running a pornography site.) Second, he realizes all his dreams are dashed, because his benefactor is not Miss Havisham. This means that she is not grooming him as Estella's husband. Third, Pip realizes he has been horribly snobbish and superior to Joe and Biddy for no reason. It was one thing when he thought his wealth was coming from a lady who, though very strange, was upper class and had inherited her money honestly. Now, however, Pip is flooded with shame when he realizes he looked down on Joe when his own money is, to his mind, dirty and from an unacceptable source.
As we can see, Pip has had a tremendous shock and is undergoing severe emotional turmoil. Imagery that expresses this shock includes that Pip "had to struggle for every breath." Pip also tells us,
I stood, with a hand on the chair-back and a hand on my breast, where I seemed to be suffocating,—I stood so, looking wildly at him, until I grasped at the chair, when the room began to surge and turn. He caught me, drew me to the sofa, put me up against the cushions, and bent on one knee before me, bringing the face that I now well remembered, and that I shuddered at, very near to mine.
In the passage above, Pip grows so short of breath that he becomes dizzy and begins to faint, so that Magwitch has to catch him and put him on the sofa. Pip also "shudders" as he looks at Magwitch's face. He says his "blood... r[uns] cold" when Matwitch takes his hand. All of this shows Pip's horror at his situation.
As the enormity of what has happened dawns on him, Pip states,
I began fully to know how wrecked I was, and how the ship in which I had sailed was gone to pieces.
His imagery of likening what has happened to a shipwreck brings home the extent to which he feels his life has been upended.