"God Rachel! Why can't you just stop crying and ranting and acting all hurt when we both know that your not? So what if I decided to have fun with some Cheerio? You must have expected it! You never let me touch you, you always whimper like some scared animal when I ask to stay 'round yours when your Dads are out and God forbid I suggest that we get it on because you change the subject faster than my Mum does when I bring up Dad."
Finn towered over Rachel looking every bit the lumbering giant he was. You could see the anger in his eyes, the fire growing with every word as he spoke of Rachel's behaviour. He truly believed that she was intentionally messing with him, teasing him and then rejecting him just to hurt his feelings. He believed that she was cold-hearted and was only putting up with the act of caring for him just so she could get the thrill of disappointing him when he thought he had a chance.
He wanted to make her pay, that's why he was with the Cheerio but it didn't feel enough. Sure, she looked like she was hurting but he knew it was all an act. She didn't want him, if she did she surely wouldn't have kept turning him down, would she? He wanted to grab her and force to tell him the truth by using his fists like he would with a guy, but he wasn't a monster. Just a very angry, confused and hurt boy that didn't know how to channel his emotions. So he used his words like knifes and made sure she was bleeding by the end of his speech. He said more things, mostly untrue horrible things but he wouldn't stop and he didn't care. As long as she was a quivering mess by the end of the day he didn't give a shit how he did it.
And now in his newly found rage it didn't register in his mind that he pushed her to the ground, but he did. It didn't register that it would be possible for more people than themselves to be wandering the school an hour after the bell rang, but there was. And it certainly didn't register that Santana Lopez had seen the whole thing and heard all his words, but she did. And now he had hell to pay.