I have been eating less yet i am gaining weight?

There are two options that could be occurring here, one you've started gaining more muscle, which weighs more than fat. This is plausible because you said you've been working out as of late and when working out muscle is sure to follow. Two, you've started putting on water weight, you're an 18 year old female, which means that if you're regular you will be having a period within the next 4 weeks (depending on when you had your last one of course). The slimquick is not making you fatter, however if you are not eating at all (one small meal a day or less), then when you do eat the food is going to go straight into storage so that your body and conserve it for its next starvation period. My suggestion is to try the slimquick for a month, I haven't heard much about this product as to tell you if it is harmful for you or not so please, research it if you haven't already, and continue to eat a well balances diet and exercise regularly. And remember muscle weighs more than fat so when you gain weight its not always a bad thing!