I get incredibly worked up playing vs other players

Is this just me?

I tend to avoid PVP games or game modes. This is because I get really worked up. My heart beats really fast and my pits get sweaty. If I'm gaming shirtless I can feel the sweat drip down my sides. Afterwards it always takes me a while to come down, because it's like I've just fought for my life (fight/flight response?)

And it's not due to poor skills (with PVP I'm average to decent I think) and I'm not a sore loser, I don't fly into rage mode and throw the controller into the wall or anything. It's because I take it Very. Personally.

That guy killed my character because he hates me.
They're going after my guy because they know they're better than me.
They know I'm weak and don't know how to defend myself.

I realize this is showing my insecurities; and I can easily just not play these games. I don't do these game modes often but it has happened, eg. new content comes out and I give it a try. Or in this one game, PVP experience was necessary to unlock certain skills: so in the PVP area I crouched and slowly moved across the entire map in stealth because I didn't want to deal with opposing players.

But I'm posting more because I'm wondering.. why do I react this way? Countless gamers do PVP and not all of them can be getting worked up the way I do. Does this happen to others here?