Etiquette: Interrupting your supervisor having a meeting I'm doing an internship as a high school student in a lab and am wondering about etiquette in research/life. The problem is that I interrupted my supervisor while he was having a meeting to tell him someone from another country was on the phone (I know he regularly collaborates with researchers in foreign countries). I'm wondering whether this would be perceived by him as rude. He is still in his meeting so I want to know what to say to him when he ends it. 

The details are as follows:

Due to some complications (unnecessary details) my supervisor and I have switched offices. 

At some point while I was sitting in his office, the phone started ringing. Thinking that it could be urgent and knowing he was in a different office and so may not get to checking this voicemail, I picked up the phone. It ended up being one of his collaborators from another country who asked to speak with him. I went and found my supervisor talking to someone in person, likely another of his collaborators. I assumed that because this person on the phone was calling from another country, it was important; so I tapped lightly on the door and informed him that someone from country X wants to speak with him. He told me he'd call back the person later, telling me the phone call wasn't important enough. 

In hindsight, I think I did two things wrong: (1) I picked up his phone, and (2) and I interrupted his meeting. 

My questions are:


Is what I did wrong?
How should I approach him afterwards?
Is what I did wrong?


Picking up his phone might not have been the best idea, unless he specifically asked you to do so. What if the call received was a personal one? How would you handle that? Then interrupting a meeting to relay this information was not a good idea. However, you will make many wrong decisions but it's important to learn from them.


  How should I approach him afterwards?


I advise open communication this case. Begin with an apology then continue by explaining your reason and end by asking what process he would like you to follow should this occur again in the future. Finally, ask for clarification if the answer is vague.

Example:

"Apologies for answering your phone &amp; interrupting your meeting" 

"but I believed this call would be urgent."

"If someone calls again, what would you like me to do?"

"Should I answer &amp; take a message? Should I ask them to wait? Should I interrupt you if you're in a meeting?"