Just can't get it right

I am finding this really hard and I don't know why. This scene is completely from my head and if I hadn't painted like this before, then I would think that is the problem.

I started to use a brush on the sky but I wasn't getting the look I was after. So I returned to the palette knife which was how I started off the painting and started laying on paint. Then I had an accident and smudged white paint on the dark part of the sky, so ended up painting over it. But I suddenly started painting really bold and slapped the paint on. I loved doing it. I had fun - which is the main thing - but I am still not happy with it. It feels like I have been painting this forever. I had to stop to let the paint dry as I was just smudging it all over the place.

Close up of the textures in the sky

So I left it for another night. I want to start on another painting but if I do then I know that this one will never be finished.

I'll get there I'm sure!