We have

OTB, 5 handed - all players are 200bb+ deep
Folded round, we raise to 60p (20nl), SB 3 bets to £2,
BB Calls
We 4 bet to £5.60, looking back reckon this is 2 small.
Both players call. Pot is £18.60
Flop

Checks round to us. I could check here a good amount of the time I guess.
We bet £9, sb folds, bb jams. It's £29 for us to call.
At first I thought it was a good fold. But with the Diamonds, could also have a flush draw.