No reads, small sample set.

Ignore for the moment that I should be flatting preflop, given the preflop action, what can I do post-flop?

PokerStars No-Limit Hold'em, $0.25 BB (8 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver Cards)

SB ($13.45)
BB ($26.80)
UTG ($34.80)
UTG+1 ($8.50)
MP1 ($13.20)
MP2 ($15.60)
CO ($14.85)
Hero ($29.35)

Preflop: Hero is Button with , .
UTG calls $0.25, UTG+1 calls $0.25, 1 fold, MP2 calls $0.25, 1 fold, Hero raises to $1.5, SB calls $1.40, 1 fold, UTG folds, UTG+1 folds, MP2 calls $1.25.

Flop: ($5.25) , , (3 players)
SB checks, MP2 checks, Hero bets $3.75, SB folds, MP2 raises to $7.5, Hero?

Dealing with min-raises from unknowns is really frustrating. I think most of them learned this from bucklox.