Excellent first try, you seem to have a good grasp of colours shadows, highlights and gradients, especially for your age...
Don't worry about the little colour spill-offs and artifacts, once you'll figure out the selection tools and layering, those will be gone in a flash ;-)
like the word "soft" already sais the shades have to be softer and here they look rather muddy and you should always keep the light source in mind!!
but the background is amazing and as you already said the headband is nice!
keep it up!!