gilg-
3.8lbs is a 13,300 calorie deficit/week. 1900/day.
basal rate for you, of like 18,900/week. 2700/day.
little exercise- 22,500/week, 3200/day. (I know you said you were doing some exercise. but at that size, I have to assume its quite light really. not your fault, exercise must be...