Airbrushing does take a learning curve. I teach classes at my local Hobby shop and the #1 problem that I see when it comes to painting with the AB is that the paint is not thinned properly. I started long ago with using a AB and thought that I was never going to use my airbrush again after the first couple of times but with more experience it came easier and my avatar is a good example of what I am able to do now.
Just Dont Give UP!!!
Cheers
Chuck