That's really not BIG changes. However, when you first wake up, your heart REALLY gets to work. You've changed position drastically, you've gone from being very still to moving around a good bit, and your brain is very active. You BP can vary greatly over the course of a day. My mother-in-law's has varied as much as 50 points on the diastolic and 30 on the systolic. We check her BP at least 3 times every day- after each meal. And more often based on her symptoms (she has atrial fibrillation, has had strokes, broken hip, and suffered from high blood pressure AND orthostatic hypotension at various times in the past). To really be accurate, her cardiologist recommends we take a reading, wait 5 min, and do another, wait 5 more min. and repeat again- then take the average of the three readings. I don't often do that, except when I'm really concerned about
something. But we record her BP, pulse and Oxygen saturation readings on a form I created, along with notes about
swelling, weight, breathlessness, mood, etc. And I have that info for her doctors when it's needed. It also lets me know when something isn't quite right.
If you'd like a copy of the form, just let me know.