The speaker describes a private storm of anger. Tears leave "angry tracks" down their face, and they scream into a pillow until they have no voice left for the "foul words" crowding their mind. It's a raw, physical picture of someone who has been overwhelmed and has nowhere to put the feeling except into the dark of a bedroom.
The second half turns toward an imagined listener. The speaker admits to being bitter because of their "woes," then seems unsure they've explained it well: "If that makes sense in a twisted way." They quickly insist they aren't "daft," and say their reality "merely differs" from the listener's. The poem suggests someone who fears being dismissed or judged as irrational for feeling this deeply.
The mood is tense and defensive, but also vulnerable. The title promises an explanation, yet the speaker never names what caused the pain. What they offer instead is a plea to be believed.