Also, you don't have to do any serious exercises, but you could do 50-100 crunches a day, and 50-100 reps a day, they will help tone out your body. They might not reduce your weight (because your replacing fat with muscle) but they will help thin you out and make you look nice and toned. With exercising you may not see immediate results within your two and a half weeks, but you will most definitely see progress. Eat moderate amounts, don't starve yourself. If you want to thin out a little more, you should get your metabolism going, exercise helps with that too.

If you do decide to exercise, I suggest doing 100 crunches a day, either doing 50 twice a day, or 33 three times a day, with one extra the last time (same thing with weights, you can use 3 or 5 pound weights). Saves you energy with crunches instead of sit-ups and your getting the same amount of burn. Remember though, you lift yourself with your upper body, not your hands. Your hands are only there to keep your neck straight so that you don't hurt yourself.

Hope that helped, just remember, he's your fiancé for a reason, you love him, he loves you and he already loves the way you look and the way you are. If he pokes fun at you, don't worry about that, he doesn't mean it, all men do it, they just love to see their women mad because they look cute to them. Have fun on your wedding! Smash some cake in his face! =).
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Good luck
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