2010 Ranger, 2.3, 4x2, a real "Plain Jane" truck. 140k miles.

All of a sudden today, I start it up and it starts up fine but then idle drops, runs horribly rough and stalled.

The low gas light just went on so I stopped and grabbed 5 gallons since it reminded me of the days of 'ol with some water in the gas.

I managed to get it home, it runs ok at speed, but at a stop light it almost stalled, forcing me to place it in neutral and rev the engine.

Wierd, any thoughts?

I'm not sure where to start. If it was fuel filter or fuel pump, it'd run rough at speed, but at higher speed it's ok. I can stop and let it idle, and after about 15 seconds, it starts to crap out. Odd.