The poem seems to describe being ill, when the world feels crowded and strange. In the first lines, "a great crowd comes" during days of sickness, and it arrives "to the wrong world." The crowd could be visitors, worries, or feverish thoughts, but the poem never says, and that vagueness makes the sickness feel disorienting. Nothing quite fits where it lands.
Pain, by contrast, arrives "alone," and the odd comparison to "hoped-for good luck" suggests something unsettling: pain turns up as if it were wanted, or at least expected. The speaker may be so worn down that even pain feels like a kind of visitor.
The ending is quieter. The speaker is "silent as the moonlight / entering my bed," which is gentle and still. Rather than fighting the crowd or the pain, the speaker seems to go passive and receptive. The mood is hushed, tired, and strangely calm, with a thread of unease running underneath.