Sounds kinda typical of leos, they're much more introverted and
shy in general than other species. As long as he's eating and
healthy otherwise - it wouldn't hurt to have him tested for
parasites as a general practice upon aquiring a new animal
anyway. You didn't say what kind of container/tank he's in,
if it's a glass tank, you might want to cover three sides (on
the outside) with paper to provide a more secure feeling, torts
don't like feeling suspended in the air. Covering the outside
three sides of any glass tank is my recommendation for anyone
that has to keep theirs in a glass tank for now. Provides a more
solid, secure feeling and reduces "glass stress". If he's not
in a glass tank, disregard. Anyone keeping theirs in a rubbermaid
tub or something , if you're keeping it on the floor, be cautious
of drafts from doors opening or people walking around.
You don't sound like you've had him long, and it does take weeks
for a reptile to acclimate (get used to new things), and you
and his surroundings are new. Just give him time, don't hoover
or allow any one else too dote on him too much (hard as it is to
reist since they're cute), until he's had at least 6-8 weeks to
settle in. Just make sure he's got everything he needs and some
nice hiding spaces (piles of hay are great for vanishing into),
and he'll come around, he's little now, just give him some time
and you'll get stampeded upon soon enough.