Spent two days editing a short story I wrote

I worked from 2 pm yesterday until 4 am off and on, then today I worked on it some more. It’s only a 2,200 word story, but I never knew all the work involved in preparing a manuscript for publishing. Once I was done with the rough draft, that was like one percent of the amount of work I’ve put into it so far.

I plan on submitting the story to a science fiction magazine. I’ve written longer stories I spent less time on, but I was posting those for free on the Internet.

One thing I am not strong with is the rules of grammar, I have the Elements of Style and it has helped me, as well as using Grammarly.

Has anyone else here been through this, and can give advice?
Amateur Comic Book Artist. Tools: iPad Pro (12.9 inches, 256 Gigabytes, 4th Generation) Apple Pencil