Can someone give any tips on song structure/ chord progressions?

https://distrokid.com/hyperfollow/alexjett/eat-me

This is a song I recently released and I feel like throughout it's entirety, the song doesn't feel drastically different at any point. I am having this problem with near every song I write. Does anyone have any advice? This song also may be a bit strange chord wise as I don't have much knowledge on music theory, and I know this song technically doesn't have a solid key. I just wrote what sounded good. Thank you :)