What is a specific instance in "The Black Cat" when a character experiences remorse?

The first thing that comes to mind when looking for remorse in The Black Cat is when the narrator hangs Pluto. After he hangs the cat, he says that he experienced "a half-sentiment that seemed, but was not, remorse", but before that, during the actual description of the hanging of the cat, the narrator claims that he hung the cat with "tears streaming from [his] eyes, and with the bitterest remorse". Despite the fact that the cat had done him no wrong, that it had certainly not done anything to deserve being hung, he did it anyway. He was remorseful because he knew that the cat had once loved him and also because he knew that killing the cat was a deadly sin.