Very good for a first go, whilst a longer lens would produce more 'traditional' pans with the car filling a greater % of the frame, i quite like the distant frames, its one i will be trying this year i think. For example this shot:
(not mine, stolen from POTN: member is Matt Mead)
As has been mentioned i would maybe consider trying to get a slightly less cluttered background, i might also move the car to the bottom of the frame so you have less foreground and more background/sky. I also find cars always look better from as low as you can get. If you can see their roof they dont often look amazing. Not sure why, just something i personally try to do/not do.
Look forward to seeing your 2nd attempt.