This girl canceled plans with me by saying she was too nervous so I'm going to tell her off.
What was her excuse for canceling?
She said she is nervous, but I think she is lying.
Sometimes canceling  plans is the best way to be a good friend, since she may not have presented herself in the best way if she was nervous. Give her a second chance to redeem herself.
I'm going to call her out in front of everyone. I'll make her feel so bad via public humiliation.
Would you want someone to treat you that way? If you hurt her by humiliating her in public she'll realize she did the right thing by not going out with you and anyone else you might want to go out with who hears about your action might also say no.