You captured it pretty well. Suggestion: Unless it's a really awesomelooking wave I would suggest to get something in the foreground as a subject to make your pics a little more interesting. A little color might've helped this pic, also. Keep pluggin' away, practice makes perfect.
I like the timing, but the processing feels very 'ho-hum'. The image is almost all mid-tones and needs a contrast boost so it has some actual blacks and whites.
I did a quick and dirty edit on the phone. All I did was adjusted the curve a little to look like an S. Bumped the white up, and lowered the shadow (black). Took some of the flatness out.
My first thought looking at the original was, where are the blacks and where are the whites?