Weight is not only calories in, calories out. Some people can eat anything and gain no weight. Some can eat the same or less and gain a lot of weight. More women gain weight than men, hormones play a key role in it too.
Coconut's medium chain fats are metabolized often for energy instead of stored as fats. Everyone metabolizes fats differently, coconut actually makes me hungry within a few hours and I end up eating more personally. However, all that excess energy burns right off.
If you're worried about gaining weight, try taking more coconut and record your daily weight at least twice. Exercise or walk more to maintain movement of your body. Listen to your body always, keep track of how you feel pre and post consumption. Let us know what's going on after trialing different coconut quantities and how your body reacts to them.