MightyMarc is right when he says this is a simple pre-flop fold.

But once that flop comes up you're going to have to put it all in. There's only one hand out there which is ahead and he just happened to have it.

In general it's as likely that he's got an overpair or even a set as just the exact two cards that make the nuts.

You played it fine, but you were up agaisnt a monster. It happens, don't worry you'll get your share if you continue to play right.