I was planning to go out for a bit with my brothers and we decided the time to go. It was getting close to the time so I was about to go for a shower, and my mom asked for my help with something. Without thinking(literally) I told her I needed to go shower, saying that I had to go do something right when she asked for help came off as rude.

She said it was going to be a small thing(and it was), and that saying I had to go shower right after she asked was rude

I explained that I thought it was going to be a big thing and thought I wouldn’t have much time, and she told me it’s rude to do what I did and make sure to ask next time if something is a big thing or a small thing.

TL; DR: accidentally rude to my mom who asked for help for a small thing.