Swetha,
In your case ,increase in wt can be bco'z of muscle gain.In that case U may be feeling more active and 'll be having better stamina.
Or else u may be noticing change in ur eating pattern after exercise.U may be eating more after excercise.
As the glucose in the blood get used up after the excercise,the body sends the signal of being hungary.So, we start eating more after excercise.
To prevent this condition u should drink warm water before and after excercise.