Very difficult question. It sounds to me, from what you have said that the location is okay. It takes time for people to realize that you are there. Having some regulars already is a good sign that the food is good. One week is not long enough to determine anything. The business will level out at some point and the only way to grow beyond that is to add some new food or beverage.

As long as there are still a lot more potential customers passing the cart your okay, if you reach a point where there are few new people passing bye then you have reached location saturation and then you have to decide if you are grossing enough to carry on.