You had a good timing in this shot! The background is a bit disturbing, though. because it is too much in focus. I have two suggestions for improvement:
(1) Use a larger aperture to get the background out of focus. Of course this requires very good focussing on your subject, otherwise it will get out of focus as well. In this case, this would mean thay you would have to use a faster lens (i.e. with a larger maximum aperture). Another advantage of such a lens is that autofocus will be faster.
(2) Drawback of the previous suggestion is that you may have to buy a new lens, which will be considerably more expensive than your kit zoom lens. But you may consider also suggestion (2): put your camera on shutter priority and set the shitter time to about 1/100 to 1/50 s. Now follow the dog with the camera while it is running (this is called panning). This will also make the background unsharp, due to motion blurring, while the dog will still be relatively sharp. Some parts , for example the legs, may be unsharp, but this may also be an advantage because it adds to the sense of motion. See the attachment for an example, here I applied this technique during a cycling race.
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