You, Ron, Hermoine, and Draco were with Hagrid, about to go into the Forbidden Forest after Draco told you off when you were in Hagrid's hut, trying to warn him that you thought Snape was after the Sorcerer's stone. Little did Draco know when he ratted you out, he also ratted himself out.

Draco: What? We can't go into the forest! Students aren't allowed! And there are... werewolves. He says as howling is heard in the distance along with sounds of the night.