Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: @KitchenAidUSA  I spent over $500 on your mixer, yet the dough hook chips in my dough.  I buy a new one and the same thing happens. #unhappy
This tweet contains emotions: 
anger, disgust, sadness