The speaker describes being hit by feelings so strong they feel physical, like waves breaking over them. The ocean comparison suggests something that arrives again and again and can't be argued with. What stands out is what the speaker does with all that rage: they pour it into writing. The phrase "shiny writing fits" is a nice touch, since "fits" suggests sudden, uncontrollable bursts, while "shiny" hints that the results might actually be bright or valuable, even if they come from a painful place.
There's a cost, though. The speaker ends up with "exhausted hands / And tired eyes," and the poem makes clear this isn't a one-off. It happens "almost every night" and runs until 4 am, or for as long as the "delirium" lasts. The short, plain lines make the mood feel worn out and repetitive, like a cycle the speaker knows well. It's intense but also tired, a mix of creative release and sleepless exhaustion.