Hey SB is 33/19 after 28 hands

Flop: wasn't sure what does that donk bet meant. I guess I can exclude him having a set and playing like that instead of x/r? My initial thought was that his range contains medium overpairs, some FD, OESDs (i block some like 87) and gutshots like A2, A3s, maybe he donks with some 6x, 5x? Decided to semi-bluff - I don't want any heart turn and I can hit my OESD or T for a top pair.

Turn: I now expect him having some strong hand. I'm not sure he can play FD like that so I guess he might have hit a straight or have a set. Can I call here? I need 25% but I have only 8 outs to improve (maybe 6 if he has FD?). On the other hand his range seems strong so I have implied odds if I hit. Decided to fold but wasn't sure...

Thanks