Facial flushing is caused by dilation of blood vessels in the face not related to high blood pressure. The fact that you are 35 weeks makes me think that you are probably exerting more energy just to move around, due to your watermelon sized belly, which can cause you to flush.
High blood pressure usually doesn't cause symptoms. But very high blood pressure sometimes causes headaches and shortness of breath or changes in vision. It is usually called preeclampsia during pregnancy.
Mild preeclampsia usually doesn't cause symptoms, either. But preeclampsia can cause rapid weight gain and sudden swelling of the hands and face. Severe preeclampsia causes symptoms of organ trouble, such as a very bad headache and trouble seeing and breathing. It also can cause belly pain and decreased urination.
If you are having any symptoms, I would be seen today. In the last few weeks of pregnancy blood pressure tends to spike a bit, but it doesn't usually cause problems. I am almost 37 weeks right now, and my BP spiked to 130/80 at my last appt., but even this is considered in the normal range, especially considering the fact that I am due to deliver any day. Good luck.