DO NOT SKIP ANY MEALS!!!
If you think by starving yourself from a meal, you can reduce a kilo or two, you are dead wrong.
If you skip meals, your body thinks u r in hibernating more, there it'll help you store all the fats away.
Eat 5-6 small meals a day rather than the normal 3 meals a day. This keeps your body burning food all the time, therefore indirectly increasing ur body metabolism rate. Reduce rice intake especially at nite.
If possible, during some free time from your taekwondo class, u can try to jog or do any cardio exercise for 30min.
Yogurt drinks are basically sugared drinks. Eat some solid food rather than drink those things.
You need to change your mindset.
You cant blame other ppl or give excuses when you cant slim down.
All you need is self discipline. And for now, you certainly dun have tat.