insanity weight gain

So i have been doing insanity now for 1 month and i have noticed weight gain. My derriere has also increased in size, my abs have more definition, and my legs seem to have gotten larger as well.
I am not a big person to begin with however i thought that this program was supposed to tone you out and the research i have done seems to be that individuals have lost inches and lost weight. I feel like i am at a flat line in my work out and i just need to know that there is hope fo rme out there.
I do feel like i get an extremly benificial cardio work out , the sweat puddle is evidence of that, however my concerns with the final results are at a drop off point.
I am also deployed to Afghanistan so It is almost impossible to follow the recommended diet guide. Any advice?
Thank you