I'm 27 years old, and 2 months ago (coincident with just before I had an upper endoscopy), I started experiencing symptoms of lightheadedness, dizziness, heart racing and pounding out of my chest, blurry vision, etc. I had a til table test done earlier this month that was positive for probable POTS. However, coincident with these symptoms, I also began experiencing what I would call non-anxiety "panic attacks." At times when I wake up in the middle of the night, my heart will start racing and a sense of panic floods my body. My veins feel as if they go white cold with electric charge, and I feel 'trapped' inside my body, oftentimes shaking. My brain will also often feel like it's being pulled into another dimension. It's a horrific sensation that can take 20 min to pass (I typically have to take a Xanax to get through it). There were also days when as soon as I would wake up in the morning I would instantly be filled with a sensation of panic with a racing heart. My body feels like it's constantly on the edge of fight-or-flight, but it feels entirely physiological rather than psychological (I've been meeting with a psychologist for months and had been doing really well with my anxiety, I never experienced panic attacks before). Has anyone else with POTS experienced these issues? I'm getting better dealing with my issues of lightheadedness during the days, but now I'm terrified to go to sleep at night.