can you help me formulate an answer to a colleague who is not my boss but feels entitled to tell me how I have to work?

the colleague in question feels that only her way of doing things is the right one and expects me to adapt to her way of thinking and her logic. This is tiring and burdensome because I have to force me to stop doing things automatically and efficiently, but think how she wants it done and do it her way. I work worse when this happens.

There are several ways to reach the same goal and I always adapt according to the situation at hand. I do what feels logic at the time and work my way.

I already told the charge nurse charge about it but I don't know if she had a conversation with this coworker and what was said.

The message has to be neutral and polite. What do you think of this?

I feel you believe you are my boss. You are not. Stop telling me how to work. It's tiring. You have your way of doing things, I've got mine, both equally good. Should you have a problem with this, contact the charge or manager. I'm gonna go work now.