Very high blood pressure for a pre-employment medical for student 1 year internship?

I'm 23 year old student. I am 5 foot 8 and weigh 17 stone. I am obese and realise this. Over the last few months I have lost 3 stone and have moved out of the morbidly obese category. Recently I went for a pre-employment medical for a student 1 year internship for an office based job. They tested my eyesight and hearing. They took a sample of my hair for drug testing. They also took my height, weight and blood pressure. I was shocked to see that my normal blood pressure which I had checked a couple of days before hand as 136/80, had risen dramatically to 160/94. I was extremely nervous at the time. My vision and hearing were good. But i am gutted by my rise in blood pressure and fear it has lost me the internship. Could I possibly p with such results? Could they retest me? How long does it take to lower your blood pressure?