I was mostly worried about having some short QT syndrome. Is my QT low enough for that? If it's helpful, my lowest J-point to T-peak interval (which I head is also of interest in short qt) is 130ms (take it with +/- 5% error, I measured it myself). The average J-point to T-peak would be around 150ms.
I might add that when I did the ECG, two days before, I had woken up, and while everything was fine, when I tried to stand vertically up on the bed, I felt some sharp, strong pain middle of the chest. The pain was sharp, and then decreased in intensity. If I would lie back down on the bed it would completely disappear. Stand up again, it would come back. It hurt upon breathing at first. After I stood up with it, it continued to decrease in intensity until it disappeared after about 1-2mins. I attributed it to sleeping in a bad position (as I was hugging a small pillow, which effectively crushed the middle of my chest). But of course my anxiety got me wondering, so I had the ECG.