is a hormonal
preparation having long acting contraceptive
effect.Weight gain is a known side effect of the drug. However the weight gain you have in a span of one year, is a bit more than expected. Petogen is also known to cause water retention.
I would advice you to get yourself checked by a doctor to exclude water retention ( edema) as a cause of weight gain.You may need few investigations to exclude urinary infection,hypothyroidism
which are another causes of weight
Please don't be desperate, timely advice of a doctor will manage it very well.