I know it's too late now, but keep this in mind. The body converts complex carbs into tryptophan. Also, when you eat sugar, the body produces insulin. The effect of the insulin lasts longer than the sugar high, so you'll be tired after. (I'm not sure I got the chemical names right, but I do have scientific basis behind this.)
My solution: eat cereal 15 minutes before bed and you'll probably fall asleep much faster.