Hi there! Nice paintings you have there! I see a lot of promise in you so keep practicing!
As a quick advice (i had to find out myself and it took long enough), the quality of your equipment (paper, colors, brushes) matters A LOT when painting with watercolor. So investing a little bit pays of instantly. You'll see the difference the first moment you try them out. Also check out youtube and other tutorials for tips and creative equipment ideas.
All the best!