Task: Analyze the tweet's sentiment and assign it to either 'neutral or no emotion' or one or more of the specified emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: This tweet is dedicated to my back pain, which I do not understand because I am youthful and spry. Full of life. Vivacious.
This tweet contains emotions: 
joy, optimism, sadness