Writing is not just sitting down and writing a story. It is revision after revision and edit after edit. It is a journey, no matter how much you love to write.
Every time I print out my book and review it, I still see mistakes that need to be corrected. There is no better way to find mistakes than to print it out and then read it word by word. I know this has been said a lot of times, but for a relatively new author, I need to remind myself how important that is. By reading it out loud to yourself, you will hear the cadence and tone of what you are writing. Maybe you meant to be sorrowful and it came out sarcastic. Maybe you thought you were moving the story along and it got stale. Maybe you meant to be exciting and it came out boring. ( Heaven forbid… boring!)
Take the time to print it out and read it. You will be a better writer for it.