In my estimation professional means being skilled enough and savy enough to be paid for any given service. So, yes by my definition you are a professional. Agreed...Slippery slope!
LOL...all I did was build a couple Tamiya T-55 kits, one OOB to show off a set of resin road wheels, the other to show off a T-54 backdate set. No painting was required, just nice clean build with no visible glue marks. My payment, a couple of resin conversion kits/wheels of my choice. Wasn't really difficult (thanks to a superb kit to start with), something pretty much anyone could do, I was just lucky enough to be chosen.
Let me ask you this....if someone builds a model, takes pictures all the way through the building and painting process, and uses those pictures along with an article they wrote to be put in a magazine, they they would get paid for, does that make them a professional modeler? They are getting paid for their work. Heck if I submit a photo to FSM to go in their Reader's Gallery, you get paid for it. That hardly makes a person a professional modeler in my book.
Heck, I was accused of being a professional modeler, just because I own a hobby shop. Last time I checked...owning the business didn't all of a sudden over night make me a better modeler. Would be nice if it did....but lets be realistic shall we! LOL