Don't worry about it. Grim came to me at nearly 12 weeks weighing less than 18 lbs. He didn't look bad, he was just light and lean. His last weight at 17 weeks was 35.5 lbs. Now he looks a little skinny, but is being treated for worms. He's been tested all along and was negative, I don't know how he came up positive now. Anyway, he's steadily gained weight. He's probably still going to be a big boy, but he doesn't need all that weight on a puppy body. Those joints need less weight on them. In fact, the puppy food I have him on (Innova) is made so they DON'T have big weight increases that are too much for their body. He eats well, poops well, and plays well. He's just not an overly huge pup. It's not a bad thing. They really shouldn't reach their peak weight until they're around 2. So don't put a lot of stock in the scale, as long as the pup is gaining weight. Go more by what you SEE. I saw Grim thinning out where I wasn't comfortable, and it seemed to happen in a couple days. Sure enough, he needed some meds. If you watch your pup's growth and concentrate on what you see, you'll be fine.
Wrath of Grim z Dragon
"Mr. Grim"- Threaten my handler. I dare you.