Your frustration is absolutely 100000% justified. Your kid is a kid. Your wife should know better and stop enabling water damage to the house.
You’re running on fumes. This is absolutely not sustainable, and especially not if you have a heart condition that is serious enough that your 4yo knows what to do in case anything happens to you. Clearly he still cares about you if he was trying to help.
Make amends with your son. Talk to your wife. Someone else said it too, but you have got to be on the same page to survive this insane phase of raising tiny people.
They’d be stupid not to prepare.