Initial large loss may have been mostly water. You dont say your actual weight but your caloric intake seems very low. Your body may be reacting to extreme restriction by stubbornly storing fat. Try focusing more on measurements like waist circumference and body fat percentage versus lean muscle mass, than just scale weight. Do resistance excercise but not every day and try eating more calories and carbs around these workouts. One cheat meal per week can also be beneficial if you dont go too mad.
I like the free e book available from DrClay.com This guy really seems to have it down. Suggest you take a look