I had a puppy we got off some no hopers (rscued him really) at the age of about 3 months. they had, as awful as it is, called him Snoop Dog. never was i about to be walking down the street yelling "Snoop Dog!!, Come here"
so we changed his name to Taz, but i had a bad habit of calling him "puppy, or baby'
once i stopped and stuck to Taz, he had no idea who he was. he has never ONCE come when called, if left unleashed he just runs and wont come back. so i would be careful when renaming him!!!
A good thing to feed dogs when he matures a little is dog food with RICE in it, it is Very good for them , found at woolworths usually.
good luck with the little cutie.