First I think you should tackle your fear, is it the crowded space of the fear of crashing? Personally I hate the crowds I immediately put my headphones on and watch back to back movies or read if that is tickling my fancy.

If your fear is crashing remember that if there is an in air problem you have the rest of your life to think about it.

If you must sleep, use Unisom its over the counter and usually does not have the hangover properties of Nyquil.