I push the lever a little further!

Nothing happens... except the clock on the wall moves more quickly... then the cleaner walks in and out at high speed, in a blur... the room grows dark for a few seconds... then light again... day and night are passing!

Should I push the lever the other way? Or should I bring it to a stop? Or should I push it all the way? Or should I go back to the time when I started? Or do something else?