Second day of Phentermine and only one small meal a day with large water intake. After eating small meal and drinking one beer, stood up and immediately became nauseated, sudden urge to vomit or go to bathroom. While walking to bathroom, began profusely sweating, very overheated, blurred vision, dizzy and rapid heartbeat. Someone brought me cold water and a sip of orange juice and in 10 mins all was well just exhausted. What is this?