is it normal to lose 2kgs in a month or i shud increase my workout to three times a day?

i do it in the morning for an hour and i lost 2 kgs in a month. i was thinking of working out in the evening and after dinner too...wat r ur views?
my diet has oatmeal, protein n veggies and i dont eat after 7pm....i drink lots of water throut the day...