Thanks for the encourgaing words.
Actually I got this tip for painting white from some kind person, so am happy to pass this on: If painting white, spray a light grey undercoat first. Doesn't have to be completely even, just enough that it makes the primer lighter (unless you use a grey primer in the first place. For red, spray a reddish brown or burgundy undercoat first, then the red. I've found red and white the hardest colors to aply, so this really helped me a lot and I hope it does for you!