The mouse on your computer screen starts to move around on its own and click on things on your desktop. What do you do?
Disconnect your computer from the network and tell your supervisor.
This is definitely suspicious. Immediately report the problem to your supervisor. Also, since it seems possible that someone is controlling the computer remotely, it is best if you can disconnect the computer from the network (and turn off wireless if you have it) until help arrives. If possible, don’t turn off the computer.