Ok I Was Fasting Today In Preparation For A Colonoscopy

Ok I was fasting today in preparation for a colonoscopy tomorrow. I have been keeping well hydrated all day, drinking sprite, lemonade, Gatorade etc then around 1:00 or so I started feeling light headed, numbness in fingers and tongue, shaky, went to Dr office and blood pressure was 190 over 100. EKG was done and it was normal. Blood glucose was 124. I am not on any meds, blood pressure is normal. What would cause my blood pressure to go high because of fasting ? I am better now, have eaten etc blood pressure coming down, cancelled my procedure for tomorrow.