Why does Joe go with pip too see miss Havisham in chapter 13? What is pips reaction to joes behavior at the Satis House?

Joe accompanies Pip to the Satis House the next day. Miss Havisham gives Joe twenty five guineas for Pip's service to her and thus buys Pip's indenture as a blacksmith.

Returning to Mr. Pumblechook's house, where Mrs. Joe is also anxiously waiting, Joe produces the twenty five pounds much to everyone's -- except Pip's -- joy. Caught up in the excitement, Mr. Pumblechook insists that Pip be legally bound by law and drags Pip and the entourage down to the Town Hall to be bound. Mrs. Joe then brings everyone out for dinner.

At the meal, all but Pip seem to be enjoying themselves: "...I was truly wretched, and had a strong conviction on me that I should never like Joe's trade. I had liked it once, but once was not now."

Pip's reaction;

"I am afraid I was ashamed of the dear good fellow,--I know I was ashamed of him,--when I saw that Estella stood at the back of Miss Havisham's chair, and that her eyes laughed mischievously."