A back in my belly

This guy moves. A lot. He's busy in his little room. Here and there I've felt what seemed like a foot poking extra hard into my side, or a hand pushing into my diaphragm. Tonight, though, I felt something new and incredible. There was a hard spot on the left side of my belly...it felt not unlike indigestion, a bloated stomach, etc. I wasn't thinking too much about it. I was absentmindedly running my hand along it, and suddenly realized it was his back. It was hard and so small and such a perfect little back-shaped lump. As I was stroking it, it disappeared...like he'd had enough of me. Just like that, just a second, and then he's gone swimming again...how wonderful. I feel like I'm starting to know him.