Originally Answered: How to lose weight in 3 weeks ?
Yes, actually you've already had a good plan yourself.
1. Diet control-no sugur, no fat, etc. more vege, more fruits, and fibre food etc.
2. Exercise- you're doing push ups and sit ups, I think jogging would also help. (the time per day should be decided according to your body condition, so you should make it yourself...)
3. Willpower-stick to the end or all efforts end in vain.
Weight loss is really a time/energy-consuming, but the decisive people can always make it! Maybe, 3 weeks time is not enough for losing a lot, but it will reduce some wight.
Hope this helps.