Is it common for teenagers to have high blood pressure? i think mine is normal, but i have a family history of high blood pressure so i was concerned?

Not common. A family history increases the risk of developing hypertension. This gives you the advantage of taking appropriate precautions such as reducing salt intake, exercising on a regular basis, controlling your weight so that you decrease the risk of developing hypertension or modifying its severity. Take the family history as an incentive to do the right thing. Good luck.