Is this a good idea?

I lost 2.8 pounds at Friday's weigh in, which is great, but not as great as it sounds. I missed 2 weeks so it is for the whole time. I am really feeling like I need to stir things up and lose a little more than that.
I am going to eat only fruit, veggies, lean meat and limited whole grains for this week. I have been eating too much low fat ice cream and some sugary snacks. I know it is defeating my goals and I think if I go back to basics I will lose faster.
I am also increasing my exercise from none, lately, to everyday. I know I will see an initial gain (because I always do when I increase activity.
My question is... I know eating a low carb (bad carb) diet will increase my weight loss but are there any downfalls in doing so? Will I gain back as soon as I have ice cream again? I have been going at a steady pace, but so so so slow. I am thinking a couple weeks of cutting out the white sugar will really motivate me. I have taken my measurements and in losing 35 pounds (to date) I have also lost a total of 20.5 inches off of my waist, hips, bust, thighs, and arms and decreased from a size 20W to a snug 14(misses). My clothes that were very tight on me when I started are now falling off, and I can no longer wear them. It is a great feeling, but suddenly I want more, I want it faster. I have been getting many positive comments and that feels good but also makes me want it faster.
Anyone else experience this? Any tips or suggestions? I really feel motivated and really want o take advantage of this burst of motivation in the best way possible. Thanks for leaving your tips and comments, I read them over and over, they really make a difference for me!