Yes i think you can raise more on the turn you have the nuts. The pot is 17bb then sb bets another 6bb making it 23bb. When you raise you see his 6bb bet making the pot 29bb. You put 20bb into the pot on the turn but only 14bb was a raise the other six was to match villains bet so you were raising 14bb into 29bb on the turn with the nuts. I would have raised around 22bb here considering his donk i think he has a strong made hand and you'll get plenty of calls. 6bb + 22bb 0.12 + 0.44 = 0.56 i would have raised to around 0.56c on the turn.