Being left at school for two hours because the answering machine didn't record the message when you called and asked to be picked up, and then screamed at for not calling more times and lied to about the last time you were left someplace when you finally are picked up.
When your violin still isn't fixed, even though you were told it would be ready several days ago. I'm going into withdrawal, especially since I got a bunch of wonderful new music to play which I can't until I get the violin back, since a lot of it isn't really suited to the penny whistle.