It looks choppy. Maybe make it loop? Otherwise, have a longer pause between the sways.
Usually people sway their hand two or three times (like "uh-uh" or "uh-uh-uhh") with no pause, then pause. Your hand pauses after every sway.
I feel the motion is a bit too much for a "no-no" hand sway. At least when I make that motion, the palm of my hand moves only a little bit, maybe a pixel's worth. My finger moves a bit more (which would be exaggerated for animation). In your animation, the entire hand rotates so much, it feels more like a hand pointing to different things, or to a range of objects. However, before trying to make the hand sway less, I recommend playing with the number of sways and the lengths of the pauses between them, it might read just fine with just that adjusted.
People do not usually associate the colour blue with "no". Maybe red would work better? That way, the cursor will read at a glance, quicker even than the animation can fully play.