Can you take a break now?

So, today I played piano in my study hall. To me, I guess playing just relieves stress/calms my nerves. Today had been a great day, until my school's Dean of students poked his head in and said "can you take a break now?" I don't know what to think. A break from what? Enjoying my short break? Using my mind? Being creative? I'm trying to do something prolific, rather than sitting outside and being a vegetable. Sadly, with no work to do, I'm expected to either sit silently or quietly chat with others in the school lounge. I want to do more. I only say this because today I thought about Descartes' quote "I think, therefore I am." If I don't think, what am I? Yeah, I could concentrate more about school, but being a semi-rebellious highschooler, I want a break to do something new.