I would think you might be UNDERsalted… you body wants higher ionic concentration in the internal bodily fluids, and if you’re not consuming enough salts, it will need to shed water to build the concentrations up.
Gatorade has all sorts of salts in it – so that would make sense for why it helped you feel better.
I’m not saying this IS the answer… but something to consider, and maybe experiment around.
You might also want to check your blood pressure when you have episodes like this, to make sure it’s not too high or too low, also.