Paul's poem is about being caught in feelings that pull in opposite directions. The speaker tells someone that they "kill me" and yet "save my life" each time they appear. They say "I hate you," but their heart flutters when this person speaks. These contradictions pile up line by line, and the speaker never tries to untangle them. That seems to be the point: the feeling is too tangled to sort out.
The ending turns more sad. The person is "happy," yet thinking of them makes the speaker cry, which suggests the speaker may be left out of that happiness, or hurting while the other person moves on. That is an inference from the text, but it fits the ache of the poem.
The title, "send help," returns in the final lines with a quiet admission: "I can't do it myself." The mood is raw, a little desperate, and very honest. It sounds like someone texting at a low moment, too overwhelmed to pretend they're fine.