I find these discussions fascinating. I am a nurse. This particular statement you made is haughty and inaccurate. Nurses learn a completely different (and less rigorous) side of patient care that is vital to the success of the healthcare team. That is one reason I want to go to medical school and not NP. However, it makes me sad that medical students and doctors are so ill-informed of what nurses actually DO know and can do. In my facility I have never heard nurses "brag about how they school doctors."
But nurses know and see a different side of the patient and I hope you will learn to respect and appreciate that.
Look around. Do you actually hear nurses bragging? Or did you just see that on t.v.?
I've never heard a DNP request to be called doctor and I think the OP could use this encounter to open a conversation with that person to discuss this professionally. "Hi, thank you for your work with me today. I wanted to ask you about something that suprised me....." There is a way to address this professionally and forge relationships rather than isolating begrudging walls. By posting this on here, you continue to spread false notions about nurses that will damage others' future relationships.