Hi Lem, no you aren’t doing anything wrong here at all. Lots of players snap the forearm slightly more or less extensively, just down to variety on techniques. If you watch lots of the Chinese players they tent to really straighten put the arm on the backswing and European players in general have a more 90 degree angle through the shot. Of course all players are slightly different and it comes down to personal feeling, of course within the correct technique still.
Sometimes you may find it brings less stress on your arm by not completing snapping it to 90 degrees and making sure to stay relaxed. I wouldn’t say this caused your injury though unless you have a lot of tension in your arm.
Cheers, Tom
