Three short lines, and a lot is left unsaid. The speaker seems to be preparing for a difficult conversation, going over in their head the "hard words" they may have to speak. Nothing tells us what those words are, or why they're hard, and that gap is part of what makes the poem feel tense.
The opening line is the strangest. "Da, madam I am" is odd phrasing, and it reads like a fragment of speech, perhaps a half-formed reply, a greeting, or a stumble over how to begin. "Da" could be a word in another language or a shortened form of something else, but the poem doesn't say, so it's safest to treat it as an awkward start. The broken wording suggests nerves, as if the speaker is already struggling.
The mood is quiet, hesitant and uneasy. The speaker isn't confessing or arguing yet, only dreading. The phrase "might have to say" suggests the words aren't chosen, but forced by circumstances. The poem captures that moment before a hard talk, when everything is still unspoken.