Is my puppy supposed to be doing this?

my puppy( 8 1/2 week old akc yellow lab) is super smart (I think) the other day I worked on a couple of things, sit, speak, shake and high-5, and he now does it very well. We worked on this for about a half hour one time. now he does it whenever asked and I am astonished. Is it just me or is this normal for a puppy of 8 1/2 weeks?