If your computer doesn't work, make sure it's plugged in, duh!!! I went back and checked EVERYTHING again... Contrary to what I assumed... my water heater was set to electric and drawing 14 amps as soon as I plugged in.
MY generator is rated for 23 amps and has max capacity of 25 Amps. My AC settles at around 12.5 amps and the rest of the trailer has 1 amp of other parasitic loads, add it all up including 14 amps for the water heater and you get a total of 27.5 amps... Wow. I"m surprised my generator was able to carry that type of load for almost 5 min before stalling. ...and hope I didn't damage the coils as a result of overloading.
Anyway case closed. Hopefully this helps someone else who might be overlooking the obvious.