Do wewe think this song explains how Harry feels when he likes about his parents?

Yes and no, I don't think that Harry thought his life without his parents like a world with no air, well at least until he stood before their grave in Godric's Hollow.
But wewe can say it describes how Harry felt when he Lost Sirius

I don't think so. It could be a song for how he feels when he is separated from Ginny?