High blood pressure??

Okay so I went to an urgent care for a stye that wasn’t getting any better. So when the nurse checked my blood pressure she had a surprised look on her face and told my mom I have high blood pressure for my age (I’m 17) she didn’t tell us what is was but just that my blood pressure was high for my age. I’m like really concerned about it. Does anybody know a reason why I have high blood pressure?