Why does my head voice sound unnatural/raspy?

Been singing for some years now and this is a problem that has bugged me for a long time. My head voice doesn't sound like my chest voice at all + isn't consistent, and my throat usually hurts after a while. I have to strain my voice more than usual to reach the passagio (E4), which can be heard in the video, and high registers feel hard to me, even though I can reach them. Could it be a lack of proper technique or breathing? What could I do to fix it??

Thanks in advance :)

https://reddit.com/link/1syax6s/video/6xuurvrrazxg1/player