You should give yourself a little more credit in my opinion. It's not that bad really. Using stock etc... is just the 'old school' walling style, so there's nothing wrong with that ^^. You've created a beautiful night scene, I'd only blur those stars, they're a tad too sparkly if you now what I mean.
Next is your characters. Your shading/light reflections may not be perfect, but it's not so easy to get right so I'll just say it's something that'll come over time.
Keep improving and showing us what you got! XD