Great line quality in your snail drawing! You may have been moving at too quick of a pace while working on the boots if you were feeling overwhelmed. You don't want to spend hours and hours on it, but you don't want to move so fast that you're not feeling confident in your decisions. Strike a balance between the two. It will take some experimentation. I find it helps to take a short break if I'm starting to feel shaky in my decision making as well.