You indicate
two actions of concern I believe ?
First, the "two-stage" feeling of the round being picked up from the mag and inserted into the breech, right ?
I suppose if you have a heightened sense of feel, you could be noticing the first slight bump, or hesitation, when the disconnector rail / breech-face starts to bring the round out of the mag, and then the second feeling would be as the round first contacts the feed ramp.
If you can round up an ultra slo-mo video of the way a round impacts and bounces it's way into the chamber, it is almost surprising it feeds at all, so yeah that can be felt if you concentrate.
As I say, to be noticing that, would be a very well developed sense of feel and concentration. Can't say as I ever paid attention to the exact sequence of that aspect, but I don't recall ever starting a new reload with slide closed either.
When I first load a fresh mag, I have previously retracted and locked back the slide. For the second mag of course the slide is automatically locked back on "last round fired". (Provided the mag and slide lock did their job.) I then release the slide with a "slingshot" usually, but sometimes also with depressing the slide lock.
For your other concern about checking to make sure a round actually stripped and then have hesitation to go into battery; I would expect the short interval of slide travel and being near the end of the recoil spring's travel would be the reason. Let the rails wear in and get the gun fully broken in and I doubt that would be noticed anymore.
If your "plunk test" round drops in and out freely, I expect your are just experiencing the "new gun...hope it's perfect" feelings we all have.
By the way, if you stop checking for sure the round chambered, and just assume it did; and take a shot, the first time it fails to shoot you will find out right quick if you have a
flinch !
... NOT checking is not advised for self defense carry of course.