I doubt that your being a HSP is responsible for low tolerance for yelling. What you report is normal. If one of the cats is his (plus, YOU walk HIS dog...) and he does not do the kitty litter and that goes on and on, a normal person would get annoyed. And, if yelled back at in response, would be upset/angry/cry. All of it is in line.

I am not saying that you are not a HSP, but just observing that one does not need to be an HSP to react the way you do.