Thank you for posting your story. The embarrassment is real but if it can make one person consider the reality of safety it’s a worthwhile thing. I’m sorry that you had to be reminded the hard way and I hope none of the rest of us have to. I wish you a full recovery with no complications and will say a prayer for you and yours.
Not so long ago I did something similar. Thankfully there were no consequences but there easily could have been. I took several pistols out to shoot including one new to me that I’d bought a while back but had not shot much. After firing all the rounds I intended to fire in this gun, I put it down and spent the rest of the time shooting another pistol. When I exhausted the ammo in that gun, I picked the first gun up again and I decided to dry fire it to practice smooth trigger control, and it went off. Luckily I was pointing it down range but I truly had no idea it was loaded. That really discombobulated me and so I took the mag out to check that the gun was now truly empty, just to make sure there would be no further surprises. The mag was empty.
Fast forward a couple days and I grab that gun from my pistol rack to clean it. racked the slide to check the chamber, and what happens? Another cartridge flies out. This rattled me more than the previous ND, because that occurred at the range and this occurred in my own bedroom.
I think, in the first instance, a light primer strike gave me a click and I just assumed that the gun was empty. Ordinarily the slide might be held open if empty but I’ve been known to ride the release occasionally on other guns and it’s a gun I’ve not shot much, and I also shoot many guns that don’t have a slide hold open; I made a bad assumption. I also got careless with checking because I shoot and handle a lot of less than reliable older guns, so when this one rattled off a dozen without complaint or obvious jam/misdeed I assumed it was working right and that any discrepancy (slide not locked back, less rounds fired than I thought I loaded) must be my inattention or error. Right attitude but a wrong application of it.
After the ND, when I’d unloaded the gun at the range, I’d neglected to check the chamber. I’d made a second bad assumption on the heels of the first… that the gun must now be empty. After my string of fire, when the gun went “click,” there were in fact 2 rounds left in the gun, and the ND resulted in chambering the last. Again, the slide wasn’t held open after the ND so I should have known or suspected another round was loaded, but my unfamiliarity with this gun let me miss this. Still, it comes back to safety. One should know one’s gun to identify correct and incorrect behavior, but one should always check the gun thoroughly too. What I did right, in both cases, was to make sure the gun was pointed in a safe direction, to know my target and what was behind it, and in the second case, to “assume the gun is loaded” and check, even though I “knew” the gun was unloaded. Following the rules resulted in a good scare but no holes in anything that shouldn’t have them and no tragic accidents. But it could easily have been a different story.