Hi Lucy and welcome to WW
Been offline for a few days, and everyone's said what I'd have said - and you're doing all the things I might have suggested!
I've no idea about you, obviously ;) but my experience of aspiring writers who do a lot of professional and business writing - or indeed many other writers who are starting out - is that it can be hard to kick over the traces of everything having to be well-explained, clear, properly punctuated, grammatically correct, and so on... It's not, obviously, that those things don't matter, it's that what you're trying to do with the words, punctuation, grammar etc. is a different thing: you're trying to work on the reader, not just convey information, and focussing on getting it "right" in the first draft isn't necessarily the best way to do that. This was a blog post of mine ages ago about that, which you might find interesting: