I never liked the word weight loss. It assumes the scale is all important and any indication that the dial has moved upwards means failure.
Overall weight loss and gain can occur from so many factors it will drive anyone insane.
Fat loss on the other hand is ideal. Using the mirror/photos to track progress as well as body fat tests ensures progress is made correctly to optimise your body shape and tone.
On my program the main goal is to increase or at least maintain lean muscle mass and at the same time decrease fat mass. This occurs over time, often months of work.
Significant fat loss does not occur in 7, 10 or even 21 days.
The crash diets you see in ads of people losing 7kg in 7 days is not fat loss, its weight loss. A massive calorie deficit often accompanied by extreme exercise causes large amounts of muscle deterioration, dehydration and glycogen depletion and maybe 1kg of fat. But the damage done to the metabolism, hormones and overall health is far from worth it.
Taking 2 steps back to go 1 step forward is not the way.
Think of where you want to be in 3 months, and then 3 years. Then take the steps that will get you there.