Two questions open this tiny poem, and they are almost the same: "Who are you? Who am I?" The speaker isn't only asking about the other person. By putting "I" in the question, they admit they don't fully know themselves either. Identity feels uncertain, and the other person seems to be the only one who might supply an answer.
Then comes the demand, "Tell me!", with its exclamation mark and the space before it, which makes it sound urgent, even a little desperate. But the ending softens everything. "I might just believe / you" is hesitant and open. The word "just" suggests the speaker is willing, maybe even longing, to be convinced. The line break before "you" leaves a small pause, as if the speaker is holding back trust and then offering it.
The mood is intimate, vulnerable and tentative. It reads like a quiet conversation between two people who are still figuring each other out.