Legitimate Play?

[Gaiteka]

I am a new referee (only started at the end of last year). I ref in Australia at our local association, therefore we use 2-man mechanics and FIBA rules (not that this is a rule question).

So one of my 5 games last night was the highest level game of the night. (Men's B Grade). One of the players on team A has a history of being a hassle in the game, so my partner and I discuss that before hand and try to keep an eye on it. The game goes reasonable well for the first half. Near the end of the first half, the previously mentioned player, lets call him A1, starts yapping to B1 whilst he is preparing to take his free throws. My partner gives a stern warning to stop the chatter or they can both sit on the bench. After the final free throw, A2 shoves B2 with 2 hands in the back and I call an unsportsmanlike foul (equivalent of a FF1 I believe?). Most of the second half goes down fine, until another player from team A goes to save a ball from going out of bounds, grabs it, turns around and throws it off the head of a team B player with considerable force. I called this as a technical foul and team A protested that this was a legitimate basketball move as he was trying to retain possession of the ball.

I just wanted to ask your opinion on the matter as more experienced referees. Would you consider this a technical foul like I did? I would have let it go if the ball made contact with another part of the body, but it seemed to be deliberately aimed at the head. The game was getting heated and I thought it was best not to permit this type of play.
All opinions welcome