An isolated incident of high blood pressure is common, not finding protein in your urine is a good sign :)
I had an appt. today as well as was told I had high blood pressure. I was 145/85 (I think the bottom number was 85, I could be wrong, but 145 top number for sure, stupid pregnancy brain) I was told I'm a bit swollen around my ankles and peed In a cup and my results came out negative for preeclampsia, thank goodness, but they want to check again on my next weekly appt. If I still have high blood pressure and possibly do blood results If I have a neg. urine sample again 'cuz they said It could be some other problem Involving the Liver, didn't give me any names to go from though, I think they didn't want to scare me more than I already was/am. They told me to make sure I'm well hydrated 'cuz that may be the cause of my one time high blood pressure and not to worry. I know It's really hard not to worry, but we have to have faith! I have an u/s scheduled for tomorrow, so hopefully the both of us don't have any problems! And I'm 34+4.
That's a bit high for being pregnant, but try not to stress, that will only make it worse. My blood pressure has always been high, mine runs around 140/100 so I'm under close watch too. Your doctor is keeping a good eye on you. Try some relaxation techniques and watch your sodium intake, those both help keep mine lower.