xanthowner,
The short answer to your question is an emphatic yes, bereavement most definately will cause high blood pressure in most peole.
There is clear scientific evidence to suggest that amongst several induced physiologcal changes, stress causes the body's blood vessels to constrict, so high blood pressure will occur. The effect is pronounced in people who are more sensitve to stress, like those who worry or become anxious for relatively minor things.
In itself isolated incidences such as yours which should not be a major concern if blood pressure returns to normal in a few days.
The problem with modern day stresses however, is that they do not seem to let up, instead its like a conveyor belt of crisis upon crisis which causes the blood vessels to remain constricted and for high blood pressure to become persistent.
By modern day stresses I mean things like financial worries, job security worries, marriage or relationship problems, fear of high civil crime rates, fear of terroism etc.; 'normal' things which most of us are faced with to some degree.
The answer to tempering stress induced high blood pressure?
We must learn how to relax.
A starting point to this is perhaps to become aquainted and practice the breathing aspects of Hatha Yoga.
Use the search engines on "Hatha Youga, Breathing Exercises" to get more specific information
Wish You Good health
Bilal