What Quail said!
I had Pregnancy Induced Hypertension with my first and it is a beast. Exercise can help things and eating less salt, etc. The things you'd do for normal (non-pregnancy) blood pressure problems. The endgame for me was 7 weeks of complete bed rest to keep it from developing into pre-eclampsia (and I had to be induced at 37 weeks). If you're not spilling protein and the Dr didn't seem concerned then I wouldn't be. They can also put you on BP meds if it gets to be too much of a problem.
Probably the best thing you can do about it is NOT FREAK OUT!!
I know that's hard, but stress makes things much worse.
ETA: I meant to say that although I was on bed rest and had to be induced pretty early everything went great. I was able to deliver vaginally and my son is a happy, healthy 2 year old who's no worse for the wear. I even had a second one 22 months later (with zero complications)!
"It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood; who strives valiantly..."