Was This The Right Play?

[grandgnu]

I limp in for 400 chips UTG+1 with Q/J of diamonds (had about 4000 total chips, final table in a home game of 17 players with starting chip count of 3K)

Large stack also calls and the Big Blind checks. Flop is:

3d/6d/7h

Big blind bets 400 and I call, as does the large stack. Turn is:

7d

I now have my flush, but there's a possible house out there. Big blind (who's got me covered by a few hundred chips) bets out 1000. I go into the tank. I'm worried he's got his house, but I'm also thinking he may be protecting trips.

We have a 30 second rule to make a decision, and it's getting down to the wire, so I push all-in. Large stack folds and the Big blind calls me with 7/3 offsuit in the hole, busting me out with his house against my flush.

I almost got away from this hand, had a feeling he had the BB special. Did I make the right decision in thinking he was defending trips?