Oy vey....you might be carb sensitive, mate. Although, it might help if you define what "back on the carbs" means....a few bowls of oatmeal a day, or white bread and all that crap?
I think the problem with your last diet, and probably the reason you became especially sensitive to increased calories was that it was TOO drastic. The one thing we know about diets such as these is that they DO work....briefly. Your results are good, but unsurprising. However, they are difficult to maintain as they were achieved so quickly and so drastically. Unless you're a pro bodybuilder, don't diet like one.
This time i would emphasize a moderate carb, moderate fat, high protein diet extended over 3 months or so (still gives you time for summer) and you can gradually drop your carbs or add a fat burner as you begin to plateau. Keep lifting, of course, and 5 20-minute sessions of very intense cardio 5 times a week should do it.