Silence here is not peaceful. The speaker pictures it as an endless street lined with glass and metal, a hard, cold place that stabs rather than soothes. Being stuck on that street means being unheard, and the poem suggests the speaker cannot speak with their "own real words." The quiet outside seems to trap something loud inside.
That inner noise is the poem's sharpest tension. The speaker's skull is "broken," and thoughts fly loose, screaming and "killing." The question "can you hear them?" reads like a plea to someone who, ironically, never will, since nobody can hear a thought. By the end, only the thoughts and the broken skull remain, "mingled together" to form the speaker's being. The final word appears as "quit," likely a slip for "quiet," though it also accidentally hints at giving up.
The mood is isolated, raw, and anguished. It feels like someone describing the pain of being unable to express themselves.