Meditation will help you to stay calm. But you have to practice every day, if you only do it a few times, or one day yes two days no, you won't see any improvement. Don't be put off by the new age hippy drippy ideas about meditating. There's a lot of scientific evidence to show that, done properly, you can get great benefits. Including increases in grey matter concentration in several parts of the brain! You'll probably become a better chess player as a result. :-)
Panic attacks while playing chess

I suffer from this. My hands start shaking to the point where my opponents actually ask me if I'm feeling OK. I find the social stigma of mental illness to be too much to bear though so I tell them that I am an alcoholic and I have yet to have a drink today.

GM Walter Browne used to shake uncontrollably while playing--more so than anyone. He made it work somehow.
Beginning at 10:05 of the video https://www.youtube.com/watch?v=TLuFAVKWDeY as Walter considers Bh7+, he looks quite anxious. But I remember him shaking/moving far more than that when he was younger.

For a short period of time in OTB slow time control games I would feel much internal anxiety when I had what I thought was a winning position but the position was not so clear that I was able to relax knowing for sure I was winning. This sensation of anxiety had not plagued me previously and eventually it stopped occurring. Perhaps this was because I probably won only about half of those games.
Other than the above affliction In general I tend to be extremely relaxed while playing although I have been known to mutter self criticisms to myself when my position goes awry.

^^ ..so you thought you would make a new account and spam the forum with your grievance? Sounds rational to me.

The frustration of lag and chess.com's refusal to adjust the scores accordingly is what pisses me off the most about this site, and prevents me from coming back often.
What does this have to do with the thread topic?

Because the anger/frustration/exasperation that ALL of us suffer here from the lag can lead to panic attacks in susceptible persons.
I don't suffer from lag. I also don't get angry about a chess website, and I don't spam the forums.

pawndemonium nitrate...weigh carefully online medical talk. it could make u blow up. each indy is uneek. what may work 4dem may not work 4u.
and ste. dont do things w/ ur fingers...picking ur nose, finger drumming, itching...stuff like that.

With ADHD, it's one of the rare things that I can focus on for an extended period of time due to all the thinking involved.

Hi! Does anyone else get panic attacks when playing chess? No matter what time control, if it's a tournament game, casual game, anything, I get panic attacks. My hands start shivering, and I can feel my heart pounding faster, and even shortness of breath. It happens when I'm playing friends too. At one point my shivering was so bad that my friend actually asked me if I'm okay during the game. I'm just curious if anyone else have these problems when playing chess.
It's because you're being intellectually murdered. That's why you have panic attacks.

I have essential tremor that is magnified 1000x when I'm in time trouble. My hand shakes so bad I can only watch my time run out. I can't even pick up a mouse, let alone use it to make a move. The shaking lasts several minutes before I can start a new game. This affects bullet rating like you wouldn't believe. It's really discouraging being in a winning position, calculating all the lines, and I can't even hold onto the mouse.

¿Por qué les dirías eso?
Hi! Does anyone else get panic attacks when playing chess? No matter what time control, if it's a tournament game, casual game, anything, I get panic attacks. My hands start shivering, and I can feel my heart pounding faster, and even shortness of breath. It happens when I'm playing friends too. At one point my shivering was so bad that my friend actually asked me if I'm okay during the game. I'm just curious if anyone else have these problems when playing chess.