Can you lose 10 pounds in two weeks?

I work at a weight control office but the doctor won't prescribe me meds because of my tachycardia. So I have to go the old fashioned route and exercise. I got a gym pass five months ago, and go to the gym about four times a week. But I haven't dropped more than five pounds. This is terrible! I know I could take a diuretic before the wedding, but I really want to lose fat! I want to look semi-good for the Honeymoon, although I know Josue loves me the way I am some of those outfits I got at my shower just don't look too hot IMHO. LOL So if anyone has some fat busting tips please let me know. Thanks!