How tall are you and how much do you weigh?
Yes, losing fat quickly by starving yourself will mess up your metabolism and you will proobably gain it back and more.
Totaly restricting carbs is not the way to go. Since your working out, you need those carbs even if your trying to lose weight. I would go below 100 -150 carbs a day. Carbs and fat are not bad. Eating junk food is.
Losing weight is all a numbers game. Your body requires a certain amount of calories. This is determined by your age, height, weight, and BF%. If you go to far below your required amount, you will lose weight in the first few weeks, then it will slow down because you body thinks it's starving. Now your body will try to store food as fat because it doesn't know when it's going to get the right amount to function properly.
Losing weight the right way is a slow process. You should shoot for at least losing 1lb a week. If you realy over weight, try 2 lbs.
The best way to start is to calculate how many calories your body requires. Then how much of a reduction in calories you want in a week. 1lbs = 3500 calories a week, which is 500 calories less a day.
here is a link to a spreadsheet that will calcuate your calories.
Check it out.
Also
read this post, the whole thing.
Trust me it works. I lost over 90 lbs of fat.