Are your fans running?

there has got to be something up with either the thermostat or upper/lower hoses, there has got to be a clog. The coolat in the engine might of been able to sustain its cool with just the engine at idle, once the pump starts to gain pressure/momentium, the coolant is pressuring up, heat is adding up, temp gage rising FAST. My guess.
Remove the Tstat, for diagnostic purposes

i did mention that my motor is knocking, right?

Before or after the incident?

it is?

at this point, your engine is done. Be glad its not a 3.4 DOHC, i blew that motor the same day i bought it. How? I dont know
the 3.8L will be easily found in any parts yard for fairly cheap.

after and yes

I'm lost....so the water leaked out the drain **** and caused the overheat originally?

rebuild

My guess is that the engine is savable, but will need a full tear down.......