You’re being *way* too hard on yourself. Think loose. Really loose. Just play around with background washes for a while, and yes, mask the tighter shapes like the duck! Breathe! It’ll do what you want soon. (this from my artist mom)
Use a mask the shape of the duck that you can paint over and peel off (masking tape will do) and then you can get closer to the lines. But it doesn’t look bad. I like what I can see of the black trees.