Villain is 15/12 over 70 hands...thats all I know.

I never know what to do in these spots.
I always seem to give villain a shit load of credit and fold.

Do I call down here?

Poker Room skin
No Limit Holdem Ring game
Blinds: $2/$4
5 players
Converter

Stack sizes:
UTG: $485.00
CO: $983.20
Button: $259.20
SB: $461.70
Hero: $838.40

Pre-flop: (5 players) Hero is BB with T T
UTG raises to $15, 3 folds, Hero calls.

Flop: 4 8 5 ($32, 2 players)
Hero checks, UTG bets $21, Hero calls.

Turn: 4 ($74, 2 players)
Hero checks, UTG bets $68, Hero

His bet seems a lot bigger on the turn in relation to the pot.
What, if anything, does that usually mean?