I NEED HELP LOSING WEIGHT.?

Im 23 years old 5'4 and 245 pounds 31% body fat, Ive done slimfast, atkins, wieghtwatchers, and flat belly diets. Ive done juice diets, and fasting diets, and tried at least 5 diffrent diet pills. I had a little girl almost 2 years ago and went from 220 to 250 and just cant lose the wieght!! I eat very little carbs only whole grains, LOTS of vegetables, no salt no sugar, I work out 5 days a weeks, one day I do walking 5 miles, another I do cardio boxing and step, and another I do Yoga, another I do sit ups, push ups and so on, Than I have dance cles once a week, what am i doing wrong why cant I lose more weight???? Sorry if this isnt typed very well Im in a hurry.