What's going on? Not much. You're just growing a human, that's all!
In all seriousness, your baby is really starting to pack on the pounds and resemble an honest-to-goodness infant at this point. Although he still weighs in at only 2.25 pounds or so, he's opening his long-lashed eyes in utero and possibly even sporting a full head of heartburn-inducing hair (OK, so that last part's a rumor, but my mother had killer heartburn with my brother, and he came out looking like a chimpanzee).
Your little guy or gal is probably about 15 inches long from crown to heel, and he'll be fattening up his long, lean body in the weeks to come. So, get those fingers ready -- they're going to be pinching some chubby little cheeks in the not-too-distant future!