Like the push or am I a donk?

Party Poker - No Limit Holdem Ring game - Blinds: $0.25/$0.50 - 10 players
Converter

Stack sizes:
UTG: $55
UTG+1: $50
Hero: $48
MP1: $31
MP2: $12
MP3: $67
CO: $26
Button: $84
SB: $62
BB: $15

Pre-flop: (10 players) Hero is UTG+2 with T A
2 folds, Hero raises to $2, MP1 calls, MP2 folds, MP3 calls, 2 folds, SB calls, BB folds.

Flop: 8 A 9 ($8.50, 4 players)
SB checks, Hero bets $6, MP1 folds, MP3 raises to $15, SB folds, Hero Pushes???