I think this poem comes close to touching upon some great emotional depth. There is something very entrancing about the "(It hurts, it hurts)." You pack a lot of power between those parentheses.

However, I get a bit lost in the some vague aspects. "Emotion trickles to the floor." I know the emotion may be sadness, but let the reader feel the sadness. If you were to take out "emotion" it would read "Drip, drip, drip/trickles onto the floor." This is more effective for me - I feel the emotion without being told that it is there. Instead of an abstraction, the reader sees the scene and senses the emotion. I know it is always a struggle between being too vague and being too obvious, but I would perhaps look over the poem again and ask which words are necessary to reach the emotional core of the poem.

I would also suggest to look at "The walls close in around me." This is a phrase that has been heard in similar context before. Is there a new way to say this? Can you force the reader to experience this? This would be a magnificent opportunity to make the reader FEEL claustrophobic.

Overall, I enjoyed this poem. These are just some ideas that I hope have been constructive. It's easier to make specific suggestions like these on poems that are already quite good