I am 16 and i swim for one hour two days a week...is this enough physical activity for my age? i am 5'1" and i weight 95 lbs

Swim: Swimming is a great workout. I assume you are swimming laps and if so an hour twice a week is great exercise. Keep it up for your lifetime if possible.

Recommended: It's recommended that people have 20-30 mins of daily physical activity. Although your counting only swimming as your daily activity, you may be doing a lot of walking or physical activity that you might not be counting. I believe if you can get 3-4 hours per week of activity, you should be fine. Hope that helps.

Probably: You may want to exercise on more than 2 days and mix it up with cardio and progressive weights.

Yes: Swiming is a great sport and exercise. May be you can do it 3 time a week and this dates eat plenty of carbs.