If I stopped running for 3 days.....will my fat come back?

I have been obsessive about running for 3 months now...been doing 3,4,5 miles each night for a few months. Recently finals have been getting in the way and hawaii is going to get a large storm for the next week and I won't be able to run much, will my fat start coming back on my stomach this quick if I skip half a week or a week? I got my stomach to finally be flat and don't want that fat to return. am I being ridiculous?