Good result from a bad call. How many times have you called with a hand like that and it didn't work out? Lots for all of us, I'm sure. But like I said, it was a good result. And something that I've never seen mentioned here: the more callers in a hand, the LESS probable you are to catch your cards. It's normal to think that it is a better deal to call with marginal hands with more people in the pot, but it is not.
You got a lucky flop, but with an all in as the next move, I'd have had to think hard about a call, even then. The only possible card that gives you the stone nuts is 3s, right? Who's to say your opponent didn't raise with 67,78,89,9 10,10 J, or JQ of spades? That's a lot of cards that beat you, and if you stayed in with 45s, couldn't you already be beat? Like I said the only card you can get is the 3s for a guarantee. I'd have to think about that one before a shrug and a call, but I'm a pretty tight player, too.