My puppy shakes? Growing problems or...?

Today I noticed something odd about my 12 week old lab. First, he's BIG. Growing fast and should be a very large bird dog like his 95lb muscular father. Now. When he sits, his front leg like, trembles. Is this completely abnormal and should I get his bones and joints xrayed? Regardless I have a vet appt for Tuesday but my curiousity is getting to me. He isn't in pain but they really shake when he sits like they're weak or something. Growing? Idk. H e l p please thanks.

he might be growing so fast his little front legs cant suppost him! =p i dunno sry lol, iv seen dogs do this before tho so its probly nothing to worry abt if your alredy going to see the vet

I don't know what is wrong with your puppy as I am not a vet (and there are no vets here, at Answers, sorry) but the shaking you described is not normal. I have owned some large and very large dogs that never shook as pups and I've never seen any dog with that symptom.It *might* be Wobbler Syndrome or something else. Good luck at the veterinary clinic tomorrow. I hope your vet has good news for you.