My blood pressure seems to jump around from 140 over 83 to 160 over 100 in the course of one day. Is this anything to worry about?

Difficult to say. Blood pressure normally varies throughout the day, affected by hormonal balance, hydration status, and other factors. If taken right after climbing up the stairs, it will be substantially higher than taken at rest. A quiet, resting blood pressure of 140/90 or higher confirmed on repeat testing suggests hypertension, and warrants being followed by a doctor's office.