The speaker describes a feeling of being permanently dirty, even though the dirt isn't something you can see. Showering and scrubbing are what we normally do to get clean, but here they don't work, and the speaker already knows they won't. The line "I will never feel clean again" is final. It doesn't sound like a mood that will pass.
The poem doesn't say what caused this feeling, and that gap matters. The opening words, "and now," suggest something has happened that divides life into a before and an after, but we're left to guess what. The sense of being unclean could point to guilt, shame, or a violation, though the text doesn't tell us which. What it does show clearly is how the feeling takes over ordinary routines.
The mood is heavy, quiet, and a little numb. The short lines and plain wording make it sound like someone stating a hard fact, not crying out. The repeated, hopeless washing is what lingers.