The speaker is talking to someone they love deeply, and the poem is a plea to be allowed to care. It begins with doubt. The title, "I Probably Shouldn't," sets up the idea that this love might be unwise, and the first lines repeat "Maybe I shouldn't" as if the speaker has argued with themselves many times. They even admit that worrying about this person "could kill me," which suggests the feeling is heavy and possibly harmful.
Then the poem turns on the word "But." The speaker decides that their own safety matters less than the other person. The short, broken lines, with "You" sitting alone on its own line, make that person feel like the center of everything. The mood is tender but a little desperate. By the end, the speaker stops asking and simply states the truth: they will keep worrying whether they are allowed to or not. It reads as both devoted and slightly sad, since the love may not be welcomed.