"Nervous" should mature into "respect". Nervousness, fear and respect are related, and rightly so. Fear should mature into nervousness, and then into respect.
You're right - CCDW means there's a very dangerous machine on your person. Disrespect it, and it will disrespect you right back.
Don't become so comfortable that you lose that deep respect. That's when the negligent discharges happen.
When I first carried a loaded gun, I was walking around, stiff like a robot, making such it didn't magically go off without any notice. Paranoid that everybody could see it or could "sense" I was carrying a gun. It was absurd as I look back. But totally natural to think that way. When you first start carrying, having a gun on you 100% of the time just doesn't feel natural. But it will become natural soon enough. It will not go off on it's own, as long as you carry in a quality holster and don't fiddle with it. ND's happen when carrying with no holsters or handling the firearm/reholstering unsafely.
Never get over confident with carrying a firearm, but become comfortable and familiar enough to realize, they are only machines that will only work with your input.
Going your entire life not carrying a gun, then suddenly one day you have a loaded gun on you, it's NOT an easy transition, and impossible to be suddenly 100% comfortable with it. It obviously takes time.