Hello, I have been suffering from anxiety since two years ago. I had severe panic attacks all of 2012 and had dealt with my anxiety enough to only have a couple of attacks in 2013. Well my anxiety is back full force. I don't feel stressed too much, but my body feels differently. Since two days ago my heart rate has been 125-145 and it doesn't let up. Not even to sleep. I have a doctor's appointment tomorrow, but right now i feel like im about to die. My heart rate goes up if i make any movement at all and i start to feel lightheaded and like i can't concentrate at all. Has anyone had this before? I need to know that i'm not going to die and that i'm not the only one out there that feels like this!