Well I hate for you to take all the noob shame, so I'll throw my story into the mix too:
As a kid, I got my first shotgun (winchester 1300) with a rifled barrel. All I knew was rifles, so I grabbed some magnum slugs and headed to the gravel pit. I put 2 in the tube, chambered 1, and put a third in the tube. I knew that once I pulled the trigger, it would unlock the action, and I'd read that a portion of the gasses are used to help push the action back (I think winchester calls it "PumpAssist".
So I aimed at an old soup can and pulled the trigger. The recoil was profoundly more than I'd expected. When I gathered myself, I tried to pump in the next round but the action was still locked. "Oh great. So much for buying a maintenance free new gun." So I hit the release, ejected the empty shell, and pumped in a new shell. I fired again, and sure enough, the action was locked again. "Damn"
So again, I hit the release to eject the shell and pulled the pump back. To my surprise, nothing came out. Not only was there nothing in the chamber, but my third round wasn't even in the tube anymore. I wish I'd had a picture of what my face looked like at that moment, standing there alone in a gravel pit wondering how the heck I'd managed to do that.
As I pondered my sanity, I bent down to paw through the long grass and retrieve the one spent shell. Well lo and behold I found 2 spent shells and a live one! Then it clicked and I figured out what had happened:
Amidst the jarring recoil on my first shot, my slick leather gloved hands didn't feel the pump action release and get forced back so hard that the action bounced off he rearward limit of travel and slammed closed again with a fresh round in the chamber. When I thought I had ejected my first spent round, I was actually ejecting my second live round out and into the grass, and clambering my third round. The same thing happened with my second shot but this time there was nothing left for it to chamber.
That's when I learned the importance of a proper grip!!
For what it's worth, the gun only does this with magnum slugs. Shooting regular slugs with my hand completely off the pump will eject the shell. Shooting bird shot will just unlock the action and move back about an inch and a half. But if I keep my hand off while shooting magnums, it shoots just like a semi. I doubt it's very good for the gun though, so I haven't done it since that first experimentation day.
Cheers and happy shooting,
KJ