Draco attacked him like a cobra right after their last Potions class for the day and shoved into an empty corridor, making sure nobody was following them. If he was a bit more aggressive than necessary, sue him. Potter tried to make up for his wrongdoings, but he still rubbed Draco the wrong way. Slytherins were masters of lie and deception, however this one, a Gryffindor, acted like a snake.