25NL: Playing JJ on low flop

PokerStars No-Limit Hold'em, $0.25 BB (9 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Hero ($24.05)
Button ($6.25)
SB ($5.80)
BB ($22.80)
UTG ($28.25)
UTG+1 ($14.80)
MP1 ($9.10)
MP2 ($27.70)
MP3 ($33.10)

Preflop: Hero is CO with J, J.
5 folds, Hero raises to $1, 2 folds, BB calls $0.75.

Flop: ($2.10) 7, 3, 4 (2 players)
BB bets $1, Hero raises to $3, BB raises to $6, Hero calls $3.

Turn: ($14.10) 6 (2 players)
BB bets $7, Hero ???

villain was (20/14.5/3)
On the turn I can only put him on 77/33/44/66, AA/KK (not very likely though), a flush or air.
I think this is a fold, no?

Fold; he has a set a lot, these play quickly on flush draw boards.

I may even fold to his $6 on the flop, that may be a bit weak tho.

he made it abundantly clear he has you beat here..