Rachel is what you'd call a controllist.

She does good to hold it together while she tells the club what's going on. Kurt's less angry than she expected (he's off the hook but she still got him disqualified, even if he did lose in the end), more concerned with her and so maybe they're on their way to being friends again for real.

Mr. Schue starts in with a group lecture about integrity but Rachel is just not in the mood, so she walks out (she's been lectured once today and technically, she's not even a part of the group until week after next so it doesn't matter if she listens to that asshat's [Puck's words, not hers] lecture anyway), heading to Noah's truck to wait for him.

She doesn't start crying until she's in the passenger's seat, face buried in her hands.