no electrical on town and country but engine kept on running.Any idea?

Recently I was driving my town and country .Everything was working fine ,then the low fuel light came on.(It was low on gas). then when I tried to put my turn signal ,it wasn't working.Then I realized nothing was working(no lights,no radio,no power window etc) but engine kept on running.I pulled in to a parking lot quickly unbuckled my seatbelt and everything came back on(lights ,radio,power window etc.) Any idea.Can anyone help me.