My first "en plein air" watercolour painting

Some times when Brayden gets fussy, he and I go for a drive.He usually falls asleep soon, then I'm stuck in the car and mostly playing Candy Crush on my iphone.

A few days ago, we were going to Walmart and I grabbed a piece of paper and my watercolour palette with me. When I was in the parking lot, realized Brayden is sleeping so here came the time to try my courage and bring out the watercolour palette :)

Here is what was right in front of me:

and here is my painting:

Now I think maybe the grey walls could have been darker, shape of the tree is not quiet right and definitely more details were needed for the car, but hey A for effort. right?! ;)