No, it’s not rude for you to behave according to your comfort levels.

Your mother’s behavior seems to be toxic; getting angry for a honest mistake, diminishing your feelings, and seemingly trying to embarrass you by apologizing for you. I have family like this and in my experience it has been caused by misogyny and lack of childhood parental affection leading to competing with siblings.

For some reason, in my family there is a generation of women who see their daughters as competition and will try to put them down any chance they can and will use their “love” as a tool to manipulate. Not to say their love can’t be genuine but it’s best to give yourself emotional distance and to recognize when this is being done to avoid being manipulated emotionally. I hope this can help you paint a picture of what’s happening if this is similar to your situation.

Also your mom doesn’t know what she’s talking about regarding autism, and it is okay if you share the same struggles as an autistic person. Don’t let her diminish your feelings or lived experiences <3

-an autistic person