I don't see calling being correct here. I'd say 'folding' might actually be the correct play here. By just calling, you set yourself up for being re-raised, and very often give the other opponents excellent odds to outdraw you. The flop is VERY drawy, and you have a marginal made hand. If you just call, you encourage someone with something like just a 6 of spades to call here (backdoor flush + backdoor straight draw).

Raising isn't wrong here either. You can quite possibly have the best hand, and it'd make sense to thin the field and defend it. However, when the SB decides to check-raise two opponents, one who bet the pot (you), you know most of the time here, especially at these stakes, you don't have the best hand anymore. By calling you're basically paying a high price for draw here with likely very few outs.

Personally though, at these stakes, I'd highly consider folding 9To here. When you called, you weren't looking to hit top pair weak kicker. Since you now have top pair weak kicker, and only contributed very little to the pot, you can fold it and wait for a better spot.

Quite often you will take the pot, by the other times you'll have to fold. I don't think raising like you did is wrong because I think you'd have the best hand half the time here and just take the pot with your raise, or hold up by the river half the time. But the other half the time you'll lose the 6 BBs you contributed.

So in other words, raising isn't profitable, it's only about break even. You won't end up losing money, but you won't be gaining much either.

To summarize:
Fold - No fault here. Definitely not a bad move.
Raise - Break even play. Not bad, but not exactly great either. Only benefit would be to mix up your play (which to me isn't necessary at most 2NL tables).
Call - Horrible play. Your hand is usually not a favourite at the river with multiple opponents. So you're just contributing money to pot you'll end up losing most of the time.

The main reason folding isn't wrong is a top pair weak kicker on a heavy draw board against multiple opponents is NOT a strong hand at all. Why? What card can you expect to see on the turn, that you would actually like? Maybe a 2, 3 (non-spade). Every other card you can't like, as it either completes a flush, straight, or can give someone a better pair than yours.

The other play you can consider is actually folding 9To preflop here. 9To is a very weak holding, and you're really only looking to flop two pair or better with it when up against multiple opponents.