dude noo you don't look fat if you wanna know what fat is go look at a fat person cause you obviously don't know what fat is...your nothing close to and I've never in my life hear a guy ask if he was fat...sooo yah. bye.
Ok bro, can I assume that you workout? diet? etc... anyways there is no possble way that you can gain anything more than at most 3lbs on weight in 72 hours. Simple fact that anything other than a complex carb will take more than 72 hours to turn into a fat cell. Anyways to my point. If you eat a complex carb you will burn it off within 4 hours of eating it jsut because of your motab due to your body digestion. So I have to assume here that you are either just looking to get hit on by some girls on here for being half naked and in your boxers or the fact that your genetics are incredible- I'm leaning towards first part of the answer here. I have studied and have been in sports and nutrition for about 10 years now since HS started.