A very strong word; the verb meaning, literally, to strike out or drive away from; and so to drive out of one's senses. Hence in the general sense of great amazement. Amaze is to throw into a maze or labyrinth; and so is closely akin to the Greek word here, and is a faithful rendering.
Son (τέκνον)
Lit., child. See on Mat 1:1.
Thy father
“Up to this time Joseph had been so called by the holy child himself; but from this time never” (Alford).
Have sought (ἐζητοῦμεν)
Imperfect tense: were seeking; Mary is going over in mind the process of the search.