My normal blood pressure is around 110/70. Occasionally it is going to 160/100 on some days and having pain around center of chest and stiffness in neck. Also fainting and very often yawning almost 1 yawning per minute. Not able to sleep that day. Next day onwards pressure come down to normal. It was happened 4 times in 2 months period. No sugar. My weight is 65 kg and height is 167cm. No cholesterol problem. ECG ok. Why it is happening. Kindly suggest.