If you are working out as hard as you say you are, then you should definitely have seen and felt results within 3 weeks. May I suggest using a stairmaster for your cardio, even if you are a man, its one of the best cardio machines, it will strengthen your legs and gluts, as well as increase your stamina and endurance. I guarantee your pants will be too big for you in a couple weeks.
Start eating chicken, good source of protein, Tuna, and shrimp. They are all very filling. Stay away from snacking on unhealthy items. Try eating celery, carrots, or rice cakes. Use these as a substitute for between meals. I would also suggest not eating after 6-6:30, and making it a low carb dinner. But keep your dinners small, as you are dormant at night, the energy is not utilized the same.
I personally used protein shakes by EAS...MyoPlex..they are the best tasting shakes you will find. The vanilla cream is good if you add some frozen fruit (mixed berries) to it and some ice. The frozen fruit is actuallybetter for you than the fresh when it comes to berries, while frozen, the berries retian their anti-oxidants.
PM me if I can be of any more help.