Hey
@Girlinside,
I see the sentiments of your song, and I believe it to be a very personal song. The idea is very relatable for many people who feel as though they're not enough or something like that. I can tell that you already have a melody in mind for this, which is fine. But the structure seems a bit unorganized.
The song suggests that the POV yearns to be something they'll never be. The POV seems to be jealous of Katie, but I don't know the reason why he/she's jealous of her. Is she pretty? Is she rich? I've learned more and more since joining these kinds of forums: and the biggest advice is to show the song, not tell about it. Paint a picture of Katie and the emotions that the POV feels. At the moment, it seems very repetitive with the same words and themes.
Some parts are quite odd IMO, like:
I want - I want to cut my arms
don’t be alarmed
It's as if you're forcing a rhyme. You tend to force a few awkward rhymes like got/slot. Use Rhymezone.com. They give both great perfect/near rhymes that might be better than what you have at the moment. The cutting of the arms thing is too literal and it doesn't give the reader ease.
don’t you see my sadness I don't know who 'you' is. Is it Katie? Is it me, the reader? I think you have to be clear on what the POV's relationships are with the other people/person.
Maybe it's just me, but the day/night idea has been overused. Perhaps change it up or scrap it since it doesn't offer anything new to the reader.
This is a decent start, and I hope I can help with your song.
Rocky