I decided to re-do that sketch with some advice in mind. I really like how the gradient in the sky turned out (it's even more vibrant and smooth in person, my photo taking skills are not great). I tried making more emphasis in the sky - this composition looks better I think, though changes are small. But I struggled so much with this sketch...

Paper dried so quickly - I don't know why. I had to re-wet it 2 times and still some places are so dry, especially in the clouds. I don't know why it was like this, I tried to work quickly and still. I probably messed up by trying to blur reflection a bit and I see that the placing of the dirt is off for me.