Welcome to the family of writers, Mumbling! Not to worry, I think it's safe to say we were all once wary of publishing our very first story to the public. In a way it can be frightening, but also exciting journey. I remember my first stories were nothing special and I just did them because I enjoyed them. Now that I look back, I can't help but feel embarrassed by what my young mind created. But that's the beauty of it, I got better over time when people gave me feedback and how to improve my skills. I doubt I'd be where I am today had it not been for those people. More importantly, people here continue to support new writers in their journey.
In my mind the first story is often done to see what the author can already do, and where they might need help. Already I notice a few things that I'd like to talk about, number one being the plot. None of us expect that a new author can create a fantastic story right off the bat, but I'd recommend to go through the story by either yourself or by having someone else read it prior to publishing. Having a beta reader can be very beneficial. I didn't notice anything wrong with the grammar, but when there's a flashback sequence or the like, it is usually a good idea to try and separate them so that the reader knows which part is which. One good example is to use
italicized letters. I notice you did put scene breaks in between, so that's a bonus.
While I wasn't taken by the plot, I was glad to see that the characters themselves behave as one would expect and that you know what you're doing in this department. For your first story I'd say this was a good effort, but there's certainly room for improvement. Don't let these words discourage you. It's a part that every author has to go through and the fact that there was something I really liked in this story already says a lot about you as a writer. My advice to you is to just keep going and write more. You can only get better at something when you do it more. I don't think I'm the only one here to see the potential in you as an author.