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: I believe the work I do is meaningful; my clients would agree but at the end of the day, I feel like a pawn, lost in this chaotic world.
This tweet contains emotions: 
pessimism, sadness