noemi v, I experienced the same thing. that is so strange. i thought that eating rice would be too many carbs and cause me to gain weight, but as it happens your body needs some carbs to burn fat. I wrote a blog post about my experience here
Eating Carbs Helped Me Overcome a Weight Loss Plateau - Weight Loss Blog and you can see a really good explanation of how carbs help fat burning here
Carbohydrates Help Burn Fats - Weight Loss Blog
The only other thing I can think of is that when you moved out you started to eat differently. Perhaps your mother's cooking was better for you than you thought :). Are you still losing weight now that you're eating rice again?