What Causes Sudden Spike In Blood Pressure Level Upon Waking Up Abruptly?

I am a 75 years old man in excellent health, physically active( swimming, windsurfing, jogging ). I have been taking medication for a few years for marginal high blood pressure and cholesterol. My pressure is usually 125/75. The last exam I had ( blood test, heart condition, etc gave me a very clean bill of health) Today I was planning to go swimming at the pool for lapses, as usual, and I took an unusually substantial lunch with fried eggs and a glass of wine ,after which went for an equally afternoon nap (the wine had somehow ..knocked me off.) I was deeply asleep when I was abruptly awaken by my wife yelling something I couldn’t understand at first. It turned out she had left the stove open and the rice was burning. I got so startled for this sudden wake-up , even before knowing what it was, that my heart started racing and I felt something unusually wrong in my body. A sense of heaviness, the heart not only racing, but pounding.. I immediately took my blood pressure and I got even more startled: the first reading was a whopping 170/125. Never ever happened before! The second reading, a few minutes after was better : 145/119. Not bad for the systolic pressure, but still unusually high, especially for the diastolic reading. As a precaution, I took a 2nd blood pressure pill ( I usually take one a day) and a hot bath, after which the readings went back to normal: 120/70. I am planning to see my doctor again soon, , but in the meantime I would like to know if this sudden blood pressure hyke can be explained by the sudden wake-up, the heavy meal and the fact that the nap was in the mid-afternoon, maybe for reasons having to do with a perturbated circadian rhythm. When I nap I usually do it at around 1 p.m and I seem to recall to have had the same symptoms, but much milder after sleeping later on in the afternoon. Thanks for your comments Ittiandro