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: Because of 'failure of delivery on time', a customer has to pay 16K rupees more! - Not good @tiagotatamotors @TataMotors #unhappy
This tweet contains emotions: 
anger, disgust, sadness