Preeclampsia at 29 weeks...?

Right now I'm 29 weeks almost 30.... at my last doctor visit maybe a week ago they said my bp was starting to get a little high it was 122/86 and it really freaked me out.....I have to go have it checked again next wednesday...but since then i've been watching my salt intake...i try to get as little as possible. No caffeine and have been limiting my daily work such as cleaning and thing like that, but I was wondering does bp that has started to rise ever stop rising during pregnancy especially if you watch your diet ? Im only 30 weeks and i have 10 weeks left...is their a chance my blood pressure could just stabilize if i watch my diet? Of course, im going to talk to my doc. when i go next time, but i just needed some advice in the meantime....Also, can you still have a l birth if you're diagnosed with preeclampsia?