It isn’t the standing itself that’s the problem, it’s the being upright part that gets me, even if I’m sitting down. My reaction isn’t exhaustion, it’s a thing where I feel like I’m going to collapse, or sometimes a breathing problem where I think I’m suffocating, but I’m obviously not suffocating so it has to be in my head. I’ve had other issues ever since I was a teenager in high school that I’ve been told were in my head too, but this one is a little freaky since it’s actually affecting my physical capabilities.