Hi phuongann.
Let's do some math here.
1lb of weight=3000 calories
Your needs daily are let's say 2500 cal. w/exercise
You consumed let's say 1500 calories
So you have a deficit of 1000 calories.1/3 lb
The 8.8 lb is not only ludicrous, but unhealthy and unsustainable. Mind you, fluid loss could be the bigger part of this loss. Doesn't count. You need to stay well-hydrated all the time. take plenty of spring water 1h away from meals.
Try not to get too excited. Plan carefully and be reasonable with your approach.
A well balanced diet which includes fresh veg. and fruits,
quality proteins, healthy oils and fats and only some whole grains along with a good exercise regime, will serve you well.
Aim to lose no more than 1-2 lb per week
Best wishes,
Niko