NEED HELP. 1986 300SDL Electrical Issues

[Fiebs]

Here’s a doozy for you. This morning I drove my 1986 300SDL on a four hour round trip to St Louis. On the way back we ran into some rain. After driving through the rain several things began to happen:

1: immediately, my air conditioning quit working(was fully functioning) only getting hot air out of the defrost vents. Pressing the fan button increases flow slightly. None of the push buttons for the AC system do anything.

Upon getting home I parked the car for a while, thinking everything’s fine. I come out to start it and the battery is drained. I jump it and then:

2: My ac works for a split second before cutting off and doing the same thing again. Only now, when I press the AC buttons, my radio starts losing power intermittently, along with the same issues presented previously. Along with this, now the vehicles turn signals don’t work.

3: I parked the car, turned it off, and now when I turn the ignition the starter won’t even try to engage. All fuses look fine.

Can someone help me out? This is my main transportation right now