No way do you have an 8 weeks old GSD that weighs 2¾ lbs.
Even if he is a pituitary dwarf, that is far too light. (And pituitary dwarfs do NOT have a rosy outlook, although I do know of one who was put on medication from about 8 weeks old and achieved both CDX and UDX before the coat-&-kidneys consequences of that pituitary defect caught up with him.)
Although averages are only averages, they don't define "normal", 8 weeks old GSD males average just under 20 lbs.
If you have typed the weight correctly, your pup is about the size of a 2-3 weeks old GSD. At that age a pup can wobble-walk but not play, and is unteachable (their brain doesn't switch-on until some time during day 21). Weigh him on accurate scales (such as at your vets, or at a grain store or dairy factory) and, unless he is actually at least 12 lbs return him to the breeder and claim a refund.
If you didn't get him from his breeder, shame on you for encouraging the puppy-millers who supply pet shops.
8 weeks old puppies are 100%ers - they're either giving life 100% of their energy (lots of chewing & tugging) or they are 100% asleep.
Because you should not attempt to keep a GSD as small as you state, I'm not going to attempt to give diet details.
If the weight you stated is a typo that you carelessly didn't check before posting the question, give someone a Best Answer then 20± minutes later delete the question so that it doesn't mislead other people.
Be aware that YahooAnswers is full of kids pretending to know what they're talking about. If your question is about GSDs then you should ask it in one of the 300+ YahooGroups dedicated to GSDs. To look up information about GSDs for yourself, the Links in http://pets.groups.yahoo.com/group/The_GSD_Source/ are probably your best starting point. And yes, it has a section on Size & Weight.
"Ray E":
Please give no further examples of your ignorance about "my" breed. People come here expecting that answerers will know what they're talking about. You definitely do NOT, about GSDs.
Les P, owner of GSD_Friendly: http://pets.groups.yahoo.com/group/GSD_Friendly
"In GSDs" as of 1967