Exercise everyday, doing a rigorous diet and studying a lot, but when i went to see my weight i got 1 kg. what could be my problem of weight loss?

Weight loss: Weight loss requires sustain effort. Ultimately it's calories in vs. calorie out. 3,500 calories = 1 lb of human fat. Diet & exercise cause the body to lose lean tissue and water along with fat. Individual metabolic rates vary based on genetics, fitness level and size. Consider seeing a dietician and keep an accurate calorie count.

Hormones: Maria, you should get check by your physician. Possibilities include thyroid or other Hormones imbalances, pregnancy, water retention, or your diet been a high glycemic (sugar) load. If your physical exam and blood testing are okay you may need to meet with a nutritionist or exercise trainer.