Well I am not happy with my weight loss this week

I was doing good. I had lost 2 lbs as of Sunday but then we went and got ice cream as a "reward" (my first since i had started) to me and my family for helping me out. And I just had a very small cup. But that made me gain a lb. And i still hadn't lost it this morning. So I only lost 1 lb this week

I am very sad but hopefully I will do better next week. I just feel like my matabolism is non existant. Beacuse I have stuck to the diet strictly (except for that small ice cream) for 2 weeks and I have been working my butt off at the gym. I mean I don't want to it fall off to fast and I know it is a lifestyle change I just wish i would see a little better results. I guess i am just down today but i will hope and pray next week will be a good week and I guess I can't "reward" myself!
THEPICKERILLS: Has the Metformin helped at all? Is it only given if you are trying to concieve? I go back to the doctor in September so I was just curious.