Oh okay well in that case yes it is not sad but the joke is it was sad because it sounded sad or something. and I guess because at the end of the song/music video he jumps off the castle people assumed he died so people made a big deal out of it to be funny.
yes she is the queen and no the son survived and grew up to find his dad and defeat the nether king in the sequel songs ¨Take back the night¨ and ¨The dragon hearted¨