It doesn't matter how many years.
6 months after I started using PS I was working as a photo retoucher
for clients like bloomingdales, pepsi, WWE (which was WWF at the time), and a ton of catalouges.
1 year later I was a proffesional illustrator and hi end retoucher working for huge clients like
m&ms, perdue, Subway restaurants, post cereals, Kelloggs, dannon, Perrier, heineken,
Trojan, etc.
The reason I was able to turn pro so fast is because I graduated from college as an illustrator and fine artist.
I was an artist first. Trained in the classic mediums. ( oils, pencil, charcoal, guache, water colors, acrylics, etc.)
I was trained in drawing and human anatomy and life drawing and realism style painting.
Also composition, color theory, design, etc.
I did not learn PS until a year after college and I taught myself, but I didn't look at it as a computer program, I used it more like a paint brush. Just another medium or tool of art.
I didn't care about filters , plug-ins and tricks. I used the paintbrush, Airbrush, and the selection tools, especially the pen tool. To me the pen tool was just like cutting masks in watercolor or airbrush class. That and the clone tool were all I knew.
Because of color theory I was able to figure out color adjustments.
I know people who have been using PS since it first came out and they still don't create anything nice but they are very good color adjusters.
What I am saying is PS is just a tool. Learn to be an artist first and then use PS as a tool.
Don't think of it as the high tech program that if you learn it all (you won't)
then you will be an artist. ( you won't)
PS does not make you an artist. You make you an artist. PS just makes it easier to create what your artistic mind can think of.
A person who uses PS can draw a baseball and you would say " oh look, a baseball".
An artist who uses PS could create a baseball that you would want to hang on your wall.