You probably over estimated your activity level. In addition, your current weight will increase the number of calories just to maintain your weight which is the baseline for calculating weight loss.
Try using the calculator again and don’t include any activity. This will be your basal metabolic rate or the number of calories your body needs just lying in bed. Next add activity calories. Compare the difference between the calories you burn just lying in bed versus getting up and moving around.
I would think the 2000 calories diet you have been following seems reasonable, but 35 grams of fat is only 16% calories from fat which may leave you not feeling satisfied after meals. 66 grams of fat would give you about 30% calories from fat.