.15-.25 NL $25 Max

I am dealt A 5 suited spades.

I call the blind since I am in late position and there is no raise.

There are 4 players.

The flop comes up Ah 6c 5d.

I bet $2.

2 fold and the last guy goes all-in with $12.

I call.

He shows 2 pair Ad 6h.

Nothing comes up on turn/river and he wins.

Did I make the wrong call? Should I have assumed he had a set and therefore folded?

Thanks