If the PCA is there to help you and is not doing her job well, I would give your mother the examples you gave here and/or just tell your mother you do not get along well with her and she is stressing you out. Some people we like and some we do not; sounds like your PCA is not that fond of either her job or you!

My mother was in an assisted living home and needed fuller time care for awhile and my sister got her a regime of aides and one tried to keep the prize in a Bingo game that she was supposed to be helping my mother, the actual resident of the home, play! I think a lot of PCA's are under educated and not paid very well and don't "get it" about either working the job well or trying to help an actual person there in front of them.