I hate Mondays!

Last week I've booked my hotel and tickets to Munchen. I originally planed to stay there for three days (read two nights) and then come back to Erlangen and work remotely. Everything was great until today when I realized that I've made appointment for Thursday with a guy who substitutes my boss and comes to get some feedback info about me and my work. This fu... totally sucks! Booking another hotel just for one night in Munchen (it won't be cheap), re-booking the ticket (those guys at DB really know how to piss somebody off), etc. My girlfriend will be pissed of too (I promised to give her a ride to Nuernberg to the dentist on Thursday.) Why didn't I look at the calendar last week? It was all written there!! I don't get it! Oh.. I am such a... oh... no... I just hate these fu... Mondays!!!