The poem sets two ways of dealing with pain against each other. The first is a "red rave": loud, bright, physical, a place where feeling gets drowned out. The speaker admits it's "good," but the phrasing is careful. It is "seeming to be an art" to "ice all pain," so the rave looks like a skill, a way of freezing hurt until it can't be felt. That "seeming" hints the speaker doesn't fully trust it.
Then the poem turns on the word "but." Ink, the stuff of writing, "comes only / from the night." Real insight, the speaker suggests, needs darkness, quiet, and the very pain the rave tries to numb. The title makes the contrast plain: emotion on one side, understanding on the other.
The mood is cool and a little wary. The speaker doesn't scold the rave, but the short, clipped lines and the final image of night lean toward writing as the more honest route, even if it costs something.