RMC, you've just experienced a "love bite" from your PPK. It's a common thing with this fantastic, wonderful handgun which certainly does not warrant a 12 pounder being anywhere near it. It bit you because you were not holding it right.
Try this. No, better yet,
do this and both your hand
and your PPK will thank you. Go ahead, go and get it. Yes, right now before you read this any further. Go get it and hold it in your shooting hand. I'll wait...
Got it there? OK, good. Hold it as if you're ready to fire. Now, stop right there and observe the position of your thumb. See that? That's not right - and you're going to get bit that way.
Now, slide your thumb down ever so slightly
until it overlaps your middle finger slightly. Move your thumb down so the pad of your thumb lightly rests on the top edge of your middle finger. It might feel a little strange at first but that's the way one must hold their PPK or you're going to get it. Here's some pictures to demonstrate:
In this photo, you can see the "natural" way most people who haven't had much experience with PPKs hold their guns. It's a natural human grasp and feels normal. But the PPK was designed to be small and the fact that the barrel also acts as the guide rod (a genius of design) dictates a low slide. The design keeps things small, simple, and more in line with the radius bone of the forearm, which promotes accuracy. However, it also allows for "slide bite." The red arrow I put in the picture shows where the slide will get me if I hold my PPK this way.
Here's a view of the same grip. You can clearly see where I'd get a nice double bite if I held her this way. That slide comes back viciously and mercilessly when it cycles a round, and human flesh will suffer if it's in the way:
Now, if you hold your PPK the way I described above,
with your thumb slightly overlapping your middle finger on the grip, it can't get you. Try holding your PPK like this:
Same grip method, from the back. As you can see, there's no way it can get you.
Your soft tender flesh is now out of the way of the unyielding steel and your PPK will now give you a lifetime of joy. I hope this helps.
-Pilotsteve