First time in a big plane?
So what, it's not like you're going to run out of gas. Very simple: Go with the flow and either divert or declare an emergency, either way you land. Notice how neither of those things happens very often?
Save your energy for the real problems and emergencies.
Also, have you figured out yet that you usually get paid more if you fly more? Once that starts bothering your company, then they will deal with the causes. You're just the driver, just another little employee.