Don't follow Malfoy.

You're sure that Malfoy is up to something bad, but you don't want to follow him alone; you've had enough danger so far this year that you don't feel like searching out anymore. You head back up to the castle, unhappy that Malfoy is up to something, and unwilling to let it go. You realise you have too much energy, so you turn, and walk to the Quidditch Pitch, to burn it out.