I have this same reaction too. I just had a tooth pulled yesterday.(but same reaction happens every time I go to dentist) Right away after getting shots, my heart rate speeds up. Then usually on my way home the shaking will start. Yesterday, I ran the heater full blast and thought I was doing good. I went to bed and woke up about an hour and half later shaking uncontrollably. I got up and blasted the furnace up to 90 degrees and stood on top of it until the coldness and shakiness subsided some. Ended up sleeping on my heating pad. When I woke up I was fine.View Thread