Wow, where to start? A lot of things effect your blood pressure (BP)including your age, your BP will rise as the day goes on, your BP will usually get higher as you age, it can be affected by your weight and other underlying bad habits such as booze and cigs.
www.xklworldwide.com/normal_BP.html
Well I'm at work and for some reason my computer won't allow me to copy and paste so run a search on your favourite search engine normal B/P. I have typed one I found for you but the others that I found are to long to bother with.
Oh and for the record, worrying about ones BP can also raise ones BP
You might want to get some advice about the benefits of fitness and how it will positively effect your total health. Good luck.
Doctors don't always have all the answers seek out a sports Dr. and see if he/she can give you some advice.