Thank you for your advice!
The text that I’m copying was actually from another website, but I have tried copying from my notes app and from some other places, and it has the same issues.
I thought that if I pasted to the html side that it would remove the formatting (which I’d be ok with- I can recreate the spacing) but it for some reason is keeping the spacing in the editor, just not on the site. If there is a way to remove the spacing I would do it (I’ve also tried using the paste as plain text option with no luck).