I recently started counting calories and it seems to be the kind of diet that's good for me, since I have difficulty following fixed diet plans. I've a lot of weight to lose to get to my ideal weight (about 100 lbs of weight loss) and I started dieting 11 days ago. The odd part was that within those 11 days I seem to have lost almost 7 pounds! Is this normal?

I counted my BMI which is 1905 and multiplied it with the appropriate activity factor in order to create a 500 calorie deficit as I want a steady and healthy weight loss. However I'm not sure if that was the right activity level now. My lifestyle in general is sedentary right now. I'm sitting on my bed or chair for long hours and study, I don't work, I rarelly do house chores and I take the bus to and from Uni each day. My exercise is walking, about 2.5 miles per day, 5 times a week at a 2.5 mph speed. So, my question is, do I belong to a different activity level other than sedentary? Or is it normal to lose a lot of weight when starting a diet?

My original weight loss plan is to eat 500 calories less and use up another 250-500 calories with exercise, 3-5 times a week.

A big initial loss is quite normal with a big lifestyle change. It seems to be mostly water and basically should be ignored. Wait another 2 weeks and see how your weight is dropping. Really, experimentation is the only way to find the right range--you want to lose at a steady pace but not be too hungry.

Activity level does not equal exercise. Those are two different animals. You would definitely count as sedentary, like me. My job is a desk job, I come home and sit at another desk and do computer stuff. I'm largely inactive. The next level up would be a retail job where you're standing, moving some, etc.

Your loss is normal. My first week I lost 8 pounds, and it was mostly water.