The speaker is talking directly to someone they love, and the message is part warning, part plea: one day you'll miss me, and by then it will be too late. The things they list are small and ordinary, like text messages, worrying when the other person stays out late, even being "annoying." These are the quiet signs of caring that are easy to take for granted, and the speaker suspects they are being taken for granted now.
The feeling underneath is loneliness and hurt, mixed with a little bitterness. The most telling line is about having "someone who actually wanted you," which suggests the speaker feels unwanted or overlooked themselves, and fears that their love isn't being valued. The repeated "Your going to miss" works like a refrain, almost like someone saying the same sad thing over and over because they can't get it across. The mood is raw, tender and a bit heartbreaking, and the plain, unpolished language makes it feel like a real, unfiltered confession.