Bloated and still peeing vs non pissing

Okay, when you get that sloshing feeling in your stomache and you are no longer peeing, what should you take? More salt and gatorade or salt and water? If you are sloshing and still peeing then is salt all you need to get going?

Also, I didn’t pee for the entire marathon last year. Should I be concerned? I didn’t feel dehydrated.