Why is my blood pressure so high when I am only 20 years old?

I am only 20 years old and my blood pressure is high. When I do the blood pressure checks, i am always over 140 and usually over 80. Should I see a doctor or could this be normal? my most recent was 142/77 with a heart rate of 67. I am 175 pounds and 5'7.

Over 130/70 is abnormal. Which means you probably have hypertension. But your blood pressure changes throughout the day so you should only check it at the same time everyday. but over 140 is enough of a warrant for a doctor check. You probably have high blood pressure from a hereditary reason.

Don't use the electronic measures cuz they tend to be inaccurate sometimes.
You should get a physical once a year.

Don't drink too much coke, eat too much fatty foods - those all raise ur blood pressure.
Don't screw around with high blood pressure. Make a doctor appointment ASAP.
If your blood pressure is high lay off of caffeine, walk more, lose weight, lay off of salt.
See a doctor - he will tell you the proper course of action. This could be the signs of something more serious - or it could be an inaccurate reading. Only a qualified practitioner can tell you for sure