If you feel unsafe, then by all means, schedule a dealership service manager's time to drive your vehicle with you along, so they can hear what you hear, and then have them carefully inspect your vehicle for mis-aligned hood, hatch, and doors, signs of unusual wear, and accidental damage. As the recent recall 14-C03 for some C-MAX seats demonstrates, even in a modern assembly-line, there could be a missing or insufficient weld, or perhaps a door that wasn't attached 'straight'.
'Or maybe I'm just being paranoid?'
Ever felt a skyscraper sway in the wind?
Ever been stopped on one side of a large highway bridge while traffic is still moving on the other side and felt the bridge move?
Skyscraper and bridges, even with all the tons upon tons of concrete and steel, "flex" significantly with load and temperature changes, because they were designed that way.
Cars flex too.
If the car's unibody structure didn't flex at all, eventually it could crack from metal fatigue by the stresses placed on it from the changing suspension and power train loads at (relatively speaking) the 4 corners of the vehicle. Cracking would be a far worse consequence than a rubber-to-metal squeak as parts move and flex independently of one another within the original design parameters.