I wouldn't worry about energy levels too much,its negligable until you hit 90%... If you take up powerlifting, or bodybuilding then its something to think about, but its far better to place your meals around your exercise at your stage, any athlete will till food is perhaps 60% of the game.
For muscle development you need to be getting protein within an hour of exercise, preferably through a liquid because it digests faster, such as a protein suppliment, or skimmed milk. This is called the 'window of opportunity' principle. Also make sure you have eaten Carbs before you exercise, and if you are bulking eat them afterwards too. The best source of carbs is sweet potatoes, or Oats... Oats are highly underated, but us people in the know realize that if you eat enough, its the closest you will get to steroids, really the strength gains of a proper diet is incredible. Eat your carbs about an hour before you exercise, increase the time if you feel sick but the idea is to get your eating as close to your exercise as possible.
If you need anymore help regarding exercise, particualy muscle development, don't hesitate to pm me.