I would say yes, your frustration is justified. You're stuck in a situation where you are a fully grown adult without full autonomy. The dilemma is you're apparently living under your mom's roof where the control tips in her favor. Some of her control is just due to worry. Maybe it's time to start thinking about a different living situation if possible, for you and your sister. Or is there an obligation to be there for your mother? I suggest you sort out your frustrations, possibly at yourself as well as your mum, and see where your control lies regarding your living situation.