Good thing is your computer is connected, keep it. Don't touch that session.
You can find back all the command you typed, so you have the data shown you didn't shutdown the production system.
Check the alert log of the production DB, check the message file of the nachine, check crs log if using RAC, find out why the system was down.
Email and tell your manager:
As a DBA for database monitoring purpose, I have a session continuously connect to production Database. I have no problem to have somebody check my screen and find out what command I entered. The data shown it has nothing to do with the production DB down.
Enjoy.