Ok so I just made this loaf with the recipie from lesson II. I tried it with a "Tiger Bread" topping and I think that needs work but my real concern is that my loaf is rather...flat. I am happy with the color, taste and crumb but it seems awfully short and I tried a second batch and it is responding the same. What can I do different. It doubled in size both after the initial kneading and after I shaped it and let it rise for a hour before baking. What have I done wrong?