I need advice about a fight I'm having with my mom?

well I think you both are. From your point of view:yes you did tell her and you have been taking her to work and everywhere else like you said just like you argeed. She also was there when your sister and you where talking about going shopping. I think she should have told you before hand because then you girls could have figured something else out. On your mom side: My mom does this all the time I will tell her something and then she be like "you never told me that'' and then I will be like yes I did and so on. That is probraly what happend with your mom.either that or she didn't know that she had to be at work.