Painting watercolors has some unique challenges and often feels like a daredevil act. Its unpredictability as a medium is both its joy and challenge. While you can correct mistakes, you have less leeway than oils or acrylics to do so. When painting, and before putting down a brush stroke, I often take a deep breath and tell myself "it's only a piece of paper". My experience is that most all of my watercolors initially go through an ugly duckling phase that, if I tough it out, can often be transformed into something that I'm surprisingly happy with.