deep breaths from your diaphragm (push the bottom of your stomach out, don't lift your shoulders when inhaling).
Get a BP cuff, read the directions, learn how to use it (if you don't have one already). Next time you have the opportunity to get your BP checked with a manual cuff at a doctor's office, bring your battery cuff and use a few times in the same sitting to determine a rough margin of error, how large, and if it trends + or -.
The effort is worthwhile.
Also, ibuprofen?