Hello and hope you are doing well.
The nervousness could be causing the high blood pressure. There is an entity called postural hypotension, a condition in which the peripheral arteries dilate, leading to pooling of blood in the peripheries. This in effect causes decreased circulation of blood resulting in dizziness/lightheadedness. This is more pronounced if the person stands up from a lying down position. This is detected by recording the blood pressure recordings in the sitting, standing and lying down positions. If the variations in blood pressure recordings are more than 10 mmHg, it is diagnosed as postural hypotension/Orthostatic Hypotension. Check with your doctor to rule out this condition.
Hope this helped and do keep us posted.
here's a bp tracker that may help keep track of what's going on
http://www.medhelp.org/user_journals/show/284965/Blood-Pressure
I thought of the same thing with Postural hypotension I've had OH/OI for many years (36+) along with other ANS (autonomic nervous system) issues - my bp can be 70/40 with meds but normal is 90/60 and sometimes will raise to 240/120 due to my Autonomic Dysfunction issues.
Dr's wanted to treat me with meds for the raises but I said no way and after a bit it finally went back down to my "normal"