I'm the same way! Finally someone that understands it.
Mines not being locked in underwater vessels, though that does give me a bit of anxiety and makes me really uncomfortable just thinking about it

Mine is weirder? I guess
I can swim in lakes, and only if I'm not the only one in the water. But when I play video games where you have to swim in deep water where you can't see the bottom, I have an anxiety attack.
Like crying, hyperventilating, shaking anxiety attack.
But like I said, in person, as long as I'm not the only one out in water I cant see the bottom in, I'm fine. If I can see the bottom, I'm fine and can swim by myself. But if I can't see and I'm the only one in the water, I am fine at first, and then I overthink, and have a panic attack in the water. So I always have to have someone go first, and stay realitively close.

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