Could exercise be making me fatter!!!?

So I try to work out in the gym a couple times a week or go for a power walk, the thing is everytime I move around and workout even for just 20 minutes, I get realllyyyy hungry! I know its because it revs up my metabolism and becuz im burning calories, but when I get home I eat like a pig. So I feel like that when im exercising the more I eat and crave food, so im taking IN more than OUT and gaining weight!